drivers/i2c/busses/i2c-pxa.c

/* [<][>][^][v][top][bottom][index][help] */
This source file includes following definitions.
decode_bits
decode_ISR
decode_ICR
i2c_pxa_show_state
i2c_pxa_scream_blue_murder
i2c_pxa_is_slavemode
i2c_pxa_abort
i2c_pxa_wait_bus_not_busy
i2c_pxa_wait_master
i2c_pxa_set_master
i2c_pxa_wait_slave
i2c_pxa_set_slave
i2c_pxa_reset
i2c_pxa_slave_txempty
i2c_pxa_slave_rxfull
i2c_pxa_slave_start
i2c_pxa_slave_stop
i2c_pxa_slave_txempty
i2c_pxa_slave_rxfull
i2c_pxa_slave_start
i2c_pxa_slave_stop
i2c_pxa_addr_byte
i2c_pxa_start_message
i2c_pxa_stop_message
i2c_pxa_pio_set_master
i2c_pxa_send_mastercode
i2c_pxa_do_pio_xfer
i2c_pxa_do_xfer
i2c_pxa_pio_xfer
i2c_pxa_master_complete
i2c_pxa_irq_txempty
i2c_pxa_irq_rxfull
i2c_pxa_handler
i2c_pxa_xfer
i2c_pxa_functionality
i2c_pxa_probe_dt
i2c_pxa_probe_pdata
i2c_pxa_probe
i2c_pxa_remove
i2c_pxa_suspend_noirq
i2c_pxa_resume_noirq
i2c_adap_pxa_init
i2c_adap_pxa_exit
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  i2c_adap_pxa.c
   4  *
   5  *  I2C adapter for the PXA I2C bus access.
   6  *
   7  *  Copyright (C) 2002 Intrinsyc Software Inc.
   8  *  Copyright (C) 2004-2005 Deep Blue Solutions Ltd.
   9  *
  10  *  History:
  11  *    Apr 2002: Initial version [CS]
  12  *    Jun 2002: Properly separated algo/adap [FB]
  13  *    Jan 2003: Fixed several bugs concerning interrupt handling [Kai-Uwe Bloem]
  14  *    Jan 2003: added limited signal handling [Kai-Uwe Bloem]
  15  *    Sep 2004: Major rework to ensure efficient bus handling [RMK]
  16  *    Dec 2004: Added support for PXA27x and slave device probing [Liam Girdwood]
  17  *    Feb 2005: Rework slave mode handling [RMK]
  18  */
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/i2c.h>
  22 #include <linux/init.h>
  23 #include <linux/time.h>
  24 #include <linux/sched.h>
  25 #include <linux/delay.h>
  26 #include <linux/errno.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/i2c-pxa.h>
  29 #include <linux/of.h>
  30 #include <linux/of_device.h>
  31 #include <linux/platform_device.h>
  32 #include <linux/err.h>
  33 #include <linux/clk.h>
  34 #include <linux/slab.h>
  35 #include <linux/io.h>
  36 #include <linux/platform_data/i2c-pxa.h>
  37 
  38 #include <asm/irq.h>
  39 
  40 struct pxa_reg_layout {
  41         u32 ibmr;
  42         u32 idbr;
  43         u32 icr;
  44         u32 isr;
  45         u32 isar;
  46         u32 ilcr;
  47         u32 iwcr;
  48         u32 fm;
  49         u32 hs;
  50 };
  51 
  52 enum pxa_i2c_types {
  53         REGS_PXA2XX,
  54         REGS_PXA3XX,
  55         REGS_CE4100,
  56         REGS_PXA910,
  57         REGS_A3700,
  58 };
  59 
  60 #define ICR_BUSMODE_FM  (1 << 16)          /* shifted fast mode for armada-3700 */
  61 #define ICR_BUSMODE_HS  (1 << 17)          /* shifted high speed mode for armada-3700 */
  62 
  63 /*
  64  * I2C registers definitions
  65  */
  66 static struct pxa_reg_layout pxa_reg_layout[] = {
  67         [REGS_PXA2XX] = {
  68                 .ibmr = 0x00,
  69                 .idbr = 0x08,
  70                 .icr =  0x10,
  71                 .isr =  0x18,
  72                 .isar = 0x20,
  73         },
  74         [REGS_PXA3XX] = {
  75                 .ibmr = 0x00,
  76                 .idbr = 0x04,
  77                 .icr =  0x08,
  78                 .isr =  0x0c,
  79                 .isar = 0x10,
  80         },
  81         [REGS_CE4100] = {
  82                 .ibmr = 0x14,
  83                 .idbr = 0x0c,
  84                 .icr =  0x00,
  85                 .isr =  0x04,
  86                 /* no isar register */
  87         },
  88         [REGS_PXA910] = {
  89                 .ibmr = 0x00,
  90                 .idbr = 0x08,
  91                 .icr =  0x10,
  92                 .isr =  0x18,
  93                 .isar = 0x20,
  94                 .ilcr = 0x28,
  95                 .iwcr = 0x30,
  96         },
  97         [REGS_A3700] = {
  98                 .ibmr = 0x00,
  99                 .idbr = 0x04,
 100                 .icr =  0x08,
 101                 .isr =  0x0c,
 102                 .isar = 0x10,
 103                 .fm = ICR_BUSMODE_FM,
 104                 .hs = ICR_BUSMODE_HS,
 105         },
 106 };
 107 
 108 static const struct platform_device_id i2c_pxa_id_table[] = {
 109         { "pxa2xx-i2c",         REGS_PXA2XX },
 110         { "pxa3xx-pwri2c",      REGS_PXA3XX },
 111         { "ce4100-i2c",         REGS_CE4100 },
 112         { "pxa910-i2c",         REGS_PXA910 },
 113         { "armada-3700-i2c",    REGS_A3700  },
 114         { },
 115 };
 116 MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
 117 
 118 /*
 119  * I2C bit definitions
 120  */
 121 
 122 #define ICR_START       (1 << 0)           /* start bit */
 123 #define ICR_STOP        (1 << 1)           /* stop bit */
 124 #define ICR_ACKNAK      (1 << 2)           /* send ACK(0) or NAK(1) */
 125 #define ICR_TB          (1 << 3)           /* transfer byte bit */
 126 #define ICR_MA          (1 << 4)           /* master abort */
 127 #define ICR_SCLE        (1 << 5)           /* master clock enable */
 128 #define ICR_IUE         (1 << 6)           /* unit enable */
 129 #define ICR_GCD         (1 << 7)           /* general call disable */
 130 #define ICR_ITEIE       (1 << 8)           /* enable tx interrupts */
 131 #define ICR_IRFIE       (1 << 9)           /* enable rx interrupts */
 132 #define ICR_BEIE        (1 << 10)          /* enable bus error ints */
 133 #define ICR_SSDIE       (1 << 11)          /* slave STOP detected int enable */
 134 #define ICR_ALDIE       (1 << 12)          /* enable arbitration interrupt */
 135 #define ICR_SADIE       (1 << 13)          /* slave address detected int enable */
 136 #define ICR_UR          (1 << 14)          /* unit reset */
 137 #define ICR_FM          (1 << 15)          /* fast mode */
 138 #define ICR_HS          (1 << 16)          /* High Speed mode */
 139 #define ICR_GPIOEN      (1 << 19)          /* enable GPIO mode for SCL in HS */
 140 
 141 #define ISR_RWM         (1 << 0)           /* read/write mode */
 142 #define ISR_ACKNAK      (1 << 1)           /* ack/nak status */
 143 #define ISR_UB          (1 << 2)           /* unit busy */
 144 #define ISR_IBB         (1 << 3)           /* bus busy */
 145 #define ISR_SSD         (1 << 4)           /* slave stop detected */
 146 #define ISR_ALD         (1 << 5)           /* arbitration loss detected */
 147 #define ISR_ITE         (1 << 6)           /* tx buffer empty */
 148 #define ISR_IRF         (1 << 7)           /* rx buffer full */
 149 #define ISR_GCAD        (1 << 8)           /* general call address detected */
 150 #define ISR_SAD         (1 << 9)           /* slave address detected */
 151 #define ISR_BED         (1 << 10)          /* bus error no ACK/NAK */
 152 
 153 /* bit field shift & mask */
 154 #define ILCR_SLV_SHIFT          0
 155 #define ILCR_SLV_MASK           (0x1FF << ILCR_SLV_SHIFT)
 156 #define ILCR_FLV_SHIFT          9
 157 #define ILCR_FLV_MASK           (0x1FF << ILCR_FLV_SHIFT)
 158 #define ILCR_HLVL_SHIFT         18
 159 #define ILCR_HLVL_MASK          (0x1FF << ILCR_HLVL_SHIFT)
 160 #define ILCR_HLVH_SHIFT         27
 161 #define ILCR_HLVH_MASK          (0x1F << ILCR_HLVH_SHIFT)
 162 
 163 #define IWCR_CNT_SHIFT          0
 164 #define IWCR_CNT_MASK           (0x1F << IWCR_CNT_SHIFT)
 165 #define IWCR_HS_CNT1_SHIFT      5
 166 #define IWCR_HS_CNT1_MASK       (0x1F << IWCR_HS_CNT1_SHIFT)
 167 #define IWCR_HS_CNT2_SHIFT      10
 168 #define IWCR_HS_CNT2_MASK       (0x1F << IWCR_HS_CNT2_SHIFT)
 169 
 170 struct pxa_i2c {
 171         spinlock_t              lock;
 172         wait_queue_head_t       wait;
 173         struct i2c_msg          *msg;
 174         unsigned int            msg_num;
 175         unsigned int            msg_idx;
 176         unsigned int            msg_ptr;
 177         unsigned int            slave_addr;
 178         unsigned int            req_slave_addr;
 179 
 180         struct i2c_adapter      adap;
 181         struct clk              *clk;
 182 #ifdef CONFIG_I2C_PXA_SLAVE
 183         struct i2c_slave_client *slave;
 184 #endif
 185 
 186         unsigned int            irqlogidx;
 187         u32                     isrlog[32];
 188         u32                     icrlog[32];
 189 
 190         void __iomem            *reg_base;
 191         void __iomem            *reg_ibmr;
 192         void __iomem            *reg_idbr;
 193         void __iomem            *reg_icr;
 194         void __iomem            *reg_isr;
 195         void __iomem            *reg_isar;
 196         void __iomem            *reg_ilcr;
 197         void __iomem            *reg_iwcr;
 198 
 199         unsigned long           iobase;
 200         unsigned long           iosize;
 201 
 202         int                     irq;
 203         unsigned int            use_pio :1;
 204         unsigned int            fast_mode :1;
 205         unsigned int            high_mode:1;
 206         unsigned char           master_code;
 207         unsigned long           rate;
 208         bool                    highmode_enter;
 209         u32                     fm_mask;
 210         u32                     hs_mask;
 211 };
 212 
 213 #define _IBMR(i2c)      ((i2c)->reg_ibmr)
 214 #define _IDBR(i2c)      ((i2c)->reg_idbr)
 215 #define _ICR(i2c)       ((i2c)->reg_icr)
 216 #define _ISR(i2c)       ((i2c)->reg_isr)
 217 #define _ISAR(i2c)      ((i2c)->reg_isar)
 218 #define _ILCR(i2c)      ((i2c)->reg_ilcr)
 219 #define _IWCR(i2c)      ((i2c)->reg_iwcr)
 220 
 221 /*
 222  * I2C Slave mode address
 223  */
 224 #define I2C_PXA_SLAVE_ADDR      0x1
 225 
 226 #ifdef DEBUG
 227 
 228 struct bits {
 229         u32     mask;
 230         const char *set;
 231         const char *unset;
 232 };
 233 #define PXA_BIT(m, s, u)        { .mask = m, .set = s, .unset = u }
 234 
 235 static inline void
 236 decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
 237 {
 238         printk("%s %08x: ", prefix, val);
 239         while (num--) {
 240                 const char *str = val & bits->mask ? bits->set : bits->unset;
 241                 if (str)
 242                         printk("%s ", str);
 243                 bits++;
 244         }
 245 }
 246 
 247 static const struct bits isr_bits[] = {
 248         PXA_BIT(ISR_RWM,        "RX",           "TX"),
 249         PXA_BIT(ISR_ACKNAK,     "NAK",          "ACK"),
 250         PXA_BIT(ISR_UB,         "Bsy",          "Rdy"),
 251         PXA_BIT(ISR_IBB,        "BusBsy",       "BusRdy"),
 252         PXA_BIT(ISR_SSD,        "SlaveStop",    NULL),
 253         PXA_BIT(ISR_ALD,        "ALD",          NULL),
 254         PXA_BIT(ISR_ITE,        "TxEmpty",      NULL),
 255         PXA_BIT(ISR_IRF,        "RxFull",       NULL),
 256         PXA_BIT(ISR_GCAD,       "GenCall",      NULL),
 257         PXA_BIT(ISR_SAD,        "SlaveAddr",    NULL),
 258         PXA_BIT(ISR_BED,        "BusErr",       NULL),
 259 };
 260 
 261 static void decode_ISR(unsigned int val)
 262 {
 263         decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
 264         printk("\n");
 265 }
 266 
 267 static const struct bits icr_bits[] = {
 268         PXA_BIT(ICR_START,  "START",    NULL),
 269         PXA_BIT(ICR_STOP,   "STOP",     NULL),
 270         PXA_BIT(ICR_ACKNAK, "ACKNAK",   NULL),
 271         PXA_BIT(ICR_TB,     "TB",       NULL),
 272         PXA_BIT(ICR_MA,     "MA",       NULL),
 273         PXA_BIT(ICR_SCLE,   "SCLE",     "scle"),
 274         PXA_BIT(ICR_IUE,    "IUE",      "iue"),
 275         PXA_BIT(ICR_GCD,    "GCD",      NULL),
 276         PXA_BIT(ICR_ITEIE,  "ITEIE",    NULL),
 277         PXA_BIT(ICR_IRFIE,  "IRFIE",    NULL),
 278         PXA_BIT(ICR_BEIE,   "BEIE",     NULL),
 279         PXA_BIT(ICR_SSDIE,  "SSDIE",    NULL),
 280         PXA_BIT(ICR_ALDIE,  "ALDIE",    NULL),
 281         PXA_BIT(ICR_SADIE,  "SADIE",    NULL),
 282         PXA_BIT(ICR_UR,     "UR",               "ur"),
 283 };
 284 
 285 #ifdef CONFIG_I2C_PXA_SLAVE
 286 static void decode_ICR(unsigned int val)
 287 {
 288         decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
 289         printk("\n");
 290 }
 291 #endif
 292 
 293 static unsigned int i2c_debug = DEBUG;
 294 
 295 static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname)
 296 {
 297         dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno,
 298                 readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
 299 }
 300 
 301 #define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
 302 
 303 static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
 304 {
 305         unsigned int i;
 306         struct device *dev = &i2c->adap.dev;
 307 
 308         dev_err(dev, "slave_0x%x error: %s\n",
 309                 i2c->req_slave_addr >> 1, why);
 310         dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
 311                 i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
 312         dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
 313                 readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
 314                 readl(_ISR(i2c)));
 315         dev_dbg(dev, "log: ");
 316         for (i = 0; i < i2c->irqlogidx; i++)
 317                 pr_debug("[%08x:%08x] ", i2c->isrlog[i], i2c->icrlog[i]);
 318 
 319         pr_debug("\n");
 320 }
 321 
 322 #else /* ifdef DEBUG */
 323 
 324 #define i2c_debug       0
 325 
 326 #define show_state(i2c) do { } while (0)
 327 #define decode_ISR(val) do { } while (0)
 328 #define decode_ICR(val) do { } while (0)
 329 #define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0)
 330 
 331 #endif /* ifdef DEBUG / else */
 332 
 333 static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
 334 static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
 335 
 336 static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
 337 {
 338         return !(readl(_ICR(i2c)) & ICR_SCLE);
 339 }
 340 
 341 static void i2c_pxa_abort(struct pxa_i2c *i2c)
 342 {
 343         int i = 250;
 344 
 345         if (i2c_pxa_is_slavemode(i2c)) {
 346                 dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
 347                 return;
 348         }
 349 
 350         while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
 351                 unsigned long icr = readl(_ICR(i2c));
 352 
 353                 icr &= ~ICR_START;
 354                 icr |= ICR_ACKNAK | ICR_STOP | ICR_TB;
 355 
 356                 writel(icr, _ICR(i2c));
 357 
 358                 show_state(i2c);
 359 
 360                 mdelay(1);
 361                 i --;
 362         }
 363 
 364         writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
 365                _ICR(i2c));
 366 }
 367 
 368 static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
 369 {
 370         int timeout = DEF_TIMEOUT;
 371 
 372         while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
 373                 if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
 374                         timeout += 4;
 375 
 376                 msleep(2);
 377                 show_state(i2c);
 378         }
 379 
 380         if (timeout < 0)
 381                 show_state(i2c);
 382 
 383         return timeout < 0 ? I2C_RETRY : 0;
 384 }
 385 
 386 static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
 387 {
 388         unsigned long timeout = jiffies + HZ*4;
 389 
 390         while (time_before(jiffies, timeout)) {
 391                 if (i2c_debug > 1)
 392                         dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
 393                                 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
 394 
 395                 if (readl(_ISR(i2c)) & ISR_SAD) {
 396                         if (i2c_debug > 0)
 397                                 dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__);
 398                         goto out;
 399                 }
 400 
 401                 /* wait for unit and bus being not busy, and we also do a
 402                  * quick check of the i2c lines themselves to ensure they've
 403                  * gone high...
 404                  */
 405                 if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
 406                         if (i2c_debug > 0)
 407                                 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
 408                         return 1;
 409                 }
 410 
 411                 msleep(1);
 412         }
 413 
 414         if (i2c_debug > 0)
 415                 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
 416  out:
 417         return 0;
 418 }
 419 
 420 static int i2c_pxa_set_master(struct pxa_i2c *i2c)
 421 {
 422         if (i2c_debug)
 423                 dev_dbg(&i2c->adap.dev, "setting to bus master\n");
 424 
 425         if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) {
 426                 dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__);
 427                 if (!i2c_pxa_wait_master(i2c)) {
 428                         dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__);
 429                         return I2C_RETRY;
 430                 }
 431         }
 432 
 433         writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
 434         return 0;
 435 }
 436 
 437 #ifdef CONFIG_I2C_PXA_SLAVE
 438 static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
 439 {
 440         unsigned long timeout = jiffies + HZ*1;
 441 
 442         /* wait for stop */
 443 
 444         show_state(i2c);
 445 
 446         while (time_before(jiffies, timeout)) {
 447                 if (i2c_debug > 1)
 448                         dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
 449                                 __func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
 450 
 451                 if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 ||
 452                     (readl(_ISR(i2c)) & ISR_SAD) != 0 ||
 453                     (readl(_ICR(i2c)) & ICR_SCLE) == 0) {
 454                         if (i2c_debug > 1)
 455                                 dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
 456                         return 1;
 457                 }
 458 
 459                 msleep(1);
 460         }
 461 
 462         if (i2c_debug > 0)
 463                 dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
 464         return 0;
 465 }
 466 
 467 /*
 468  * clear the hold on the bus, and take of anything else
 469  * that has been configured
 470  */
 471 static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
 472 {
 473         show_state(i2c);
 474 
 475         if (errcode < 0) {
 476                 udelay(100);   /* simple delay */
 477         } else {
 478                 /* we need to wait for the stop condition to end */
 479 
 480                 /* if we where in stop, then clear... */
 481                 if (readl(_ICR(i2c)) & ICR_STOP) {
 482                         udelay(100);
 483                         writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c));
 484                 }
 485 
 486                 if (!i2c_pxa_wait_slave(i2c)) {
 487                         dev_err(&i2c->adap.dev, "%s: wait timedout\n",
 488                                 __func__);
 489                         return;
 490                 }
 491         }
 492 
 493         writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c));
 494         writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
 495 
 496         if (i2c_debug) {
 497                 dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c)));
 498                 decode_ICR(readl(_ICR(i2c)));
 499         }
 500 }
 501 #else
 502 #define i2c_pxa_set_slave(i2c, err)     do { } while (0)
 503 #endif
 504 
 505 static void i2c_pxa_reset(struct pxa_i2c *i2c)
 506 {
 507         pr_debug("Resetting I2C Controller Unit\n");
 508 
 509         /* abort any transfer currently under way */
 510         i2c_pxa_abort(i2c);
 511 
 512         /* reset according to 9.8 */
 513         writel(ICR_UR, _ICR(i2c));
 514         writel(I2C_ISR_INIT, _ISR(i2c));
 515         writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
 516 
 517         if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
 518                 writel(i2c->slave_addr, _ISAR(i2c));
 519 
 520         /* set control register values */
 521         writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
 522         writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
 523 
 524 #ifdef CONFIG_I2C_PXA_SLAVE
 525         dev_info(&i2c->adap.dev, "Enabling slave mode\n");
 526         writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c));
 527 #endif
 528 
 529         i2c_pxa_set_slave(i2c, 0);
 530 
 531         /* enable unit */
 532         writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
 533         udelay(100);
 534 }
 535 
 536 
 537 #ifdef CONFIG_I2C_PXA_SLAVE
 538 /*
 539  * PXA I2C Slave mode
 540  */
 541 
 542 static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
 543 {
 544         if (isr & ISR_BED) {
 545                 /* what should we do here? */
 546         } else {
 547                 int ret = 0;
 548 
 549                 if (i2c->slave != NULL)
 550                         ret = i2c->slave->read(i2c->slave->data);
 551 
 552                 writel(ret, _IDBR(i2c));
 553                 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));   /* allow next byte */
 554         }
 555 }
 556 
 557 static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
 558 {
 559         unsigned int byte = readl(_IDBR(i2c));
 560 
 561         if (i2c->slave != NULL)
 562                 i2c->slave->write(i2c->slave->data, byte);
 563 
 564         writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
 565 }
 566 
 567 static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
 568 {
 569         int timeout;
 570 
 571         if (i2c_debug > 0)
 572                 dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n",
 573                        (isr & ISR_RWM) ? 'r' : 't');
 574 
 575         if (i2c->slave != NULL)
 576                 i2c->slave->event(i2c->slave->data,
 577                                  (isr & ISR_RWM) ? I2C_SLAVE_EVENT_START_READ : I2C_SLAVE_EVENT_START_WRITE);
 578 
 579         /*
 580          * slave could interrupt in the middle of us generating a
 581          * start condition... if this happens, we'd better back off
 582          * and stop holding the poor thing up
 583          */
 584         writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
 585         writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
 586 
 587         timeout = 0x10000;
 588 
 589         while (1) {
 590                 if ((readl(_IBMR(i2c)) & 2) == 2)
 591                         break;
 592 
 593                 timeout--;
 594 
 595                 if (timeout <= 0) {
 596                         dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
 597                         break;
 598                 }
 599         }
 600 
 601         writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
 602 }
 603 
 604 static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
 605 {
 606         if (i2c_debug > 2)
 607                 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n");
 608 
 609         if (i2c->slave != NULL)
 610                 i2c->slave->event(i2c->slave->data, I2C_SLAVE_EVENT_STOP);
 611 
 612         if (i2c_debug > 2)
 613                 dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n");
 614 
 615         /*
 616          * If we have a master-mode message waiting,
 617          * kick it off now that the slave has completed.
 618          */
 619         if (i2c->msg)
 620                 i2c_pxa_master_complete(i2c, I2C_RETRY);
 621 }
 622 #else
 623 static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
 624 {
 625         if (isr & ISR_BED) {
 626                 /* what should we do here? */
 627         } else {
 628                 writel(0, _IDBR(i2c));
 629                 writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
 630         }
 631 }
 632 
 633 static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
 634 {
 635         writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
 636 }
 637 
 638 static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
 639 {
 640         int timeout;
 641 
 642         /*
 643          * slave could interrupt in the middle of us generating a
 644          * start condition... if this happens, we'd better back off
 645          * and stop holding the poor thing up
 646          */
 647         writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
 648         writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
 649 
 650         timeout = 0x10000;
 651 
 652         while (1) {
 653                 if ((readl(_IBMR(i2c)) & 2) == 2)
 654                         break;
 655 
 656                 timeout--;
 657 
 658                 if (timeout <= 0) {
 659                         dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
 660                         break;
 661                 }
 662         }
 663 
 664         writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
 665 }
 666 
 667 static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
 668 {
 669         if (i2c->msg)
 670                 i2c_pxa_master_complete(i2c, I2C_RETRY);
 671 }
 672 #endif
 673 
 674 /*
 675  * PXA I2C Master mode
 676  */
 677 
 678 static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
 679 {
 680         unsigned int addr = (msg->addr & 0x7f) << 1;
 681 
 682         if (msg->flags & I2C_M_RD)
 683                 addr |= 1;
 684 
 685         return addr;
 686 }
 687 
 688 static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
 689 {
 690         u32 icr;
 691 
 692         /*
 693          * Step 1: target slave address into IDBR
 694          */
 695         writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
 696         i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
 697 
 698         /*
 699          * Step 2: initiate the write.
 700          */
 701         icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
 702         writel(icr | ICR_START | ICR_TB, _ICR(i2c));
 703 }
 704 
 705 static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
 706 {
 707         u32 icr;
 708 
 709         /*
 710          * Clear the STOP and ACK flags
 711          */
 712         icr = readl(_ICR(i2c));
 713         icr &= ~(ICR_STOP | ICR_ACKNAK);
 714         writel(icr, _ICR(i2c));
 715 }
 716 
 717 static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
 718 {
 719         /* make timeout the same as for interrupt based functions */
 720         long timeout = 2 * DEF_TIMEOUT;
 721 
 722         /*
 723          * Wait for the bus to become free.
 724          */
 725         while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
 726                 udelay(1000);
 727                 show_state(i2c);
 728         }
 729 
 730         if (timeout < 0) {
 731                 show_state(i2c);
 732                 dev_err(&i2c->adap.dev,
 733                         "i2c_pxa: timeout waiting for bus free\n");
 734                 return I2C_RETRY;
 735         }
 736 
 737         /*
 738          * Set master mode.
 739          */
 740         writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
 741 
 742         return 0;
 743 }
 744 
 745 /*
 746  * PXA I2C send master code
 747  * 1. Load master code to IDBR and send it.
 748  *    Note for HS mode, set ICR [GPIOEN].
 749  * 2. Wait until win arbitration.
 750  */
 751 static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
 752 {
 753         u32 icr;
 754         long timeout;
 755 
 756         spin_lock_irq(&i2c->lock);
 757         i2c->highmode_enter = true;
 758         writel(i2c->master_code, _IDBR(i2c));
 759 
 760         icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
 761         icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
 762         writel(icr, _ICR(i2c));
 763 
 764         spin_unlock_irq(&i2c->lock);
 765         timeout = wait_event_timeout(i2c->wait,
 766                         i2c->highmode_enter == false, HZ * 1);
 767 
 768         i2c->highmode_enter = false;
 769 
 770         return (timeout == 0) ? I2C_RETRY : 0;
 771 }
 772 
 773 static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
 774                                struct i2c_msg *msg, int num)
 775 {
 776         unsigned long timeout = 500000; /* 5 seconds */
 777         int ret = 0;
 778 
 779         ret = i2c_pxa_pio_set_master(i2c);
 780         if (ret)
 781                 goto out;
 782 
 783         i2c->msg = msg;
 784         i2c->msg_num = num;
 785         i2c->msg_idx = 0;
 786         i2c->msg_ptr = 0;
 787         i2c->irqlogidx = 0;
 788 
 789         i2c_pxa_start_message(i2c);
 790 
 791         while (i2c->msg_num > 0 && --timeout) {
 792                 i2c_pxa_handler(0, i2c);
 793                 udelay(10);
 794         }
 795 
 796         i2c_pxa_stop_message(i2c);
 797 
 798         /*
 799          * We place the return code in i2c->msg_idx.
 800          */
 801         ret = i2c->msg_idx;
 802 
 803 out:
 804         if (timeout == 0) {
 805                 i2c_pxa_scream_blue_murder(i2c, "timeout");
 806                 ret = I2C_RETRY;
 807         }
 808 
 809         return ret;
 810 }
 811 
 812 /*
 813  * We are protected by the adapter bus mutex.
 814  */
 815 static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
 816 {
 817         long timeout;
 818         int ret;
 819 
 820         /*
 821          * Wait for the bus to become free.
 822          */
 823         ret = i2c_pxa_wait_bus_not_busy(i2c);
 824         if (ret) {
 825                 dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
 826                 goto out;
 827         }
 828 
 829         /*
 830          * Set master mode.
 831          */
 832         ret = i2c_pxa_set_master(i2c);
 833         if (ret) {
 834                 dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
 835                 goto out;
 836         }
 837 
 838         if (i2c->high_mode) {
 839                 ret = i2c_pxa_send_mastercode(i2c);
 840                 if (ret) {
 841                         dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
 842                         goto out;
 843                         }
 844         }
 845 
 846         spin_lock_irq(&i2c->lock);
 847 
 848         i2c->msg = msg;
 849         i2c->msg_num = num;
 850         i2c->msg_idx = 0;
 851         i2c->msg_ptr = 0;
 852         i2c->irqlogidx = 0;
 853 
 854         i2c_pxa_start_message(i2c);
 855 
 856         spin_unlock_irq(&i2c->lock);
 857 
 858         /*
 859          * The rest of the processing occurs in the interrupt handler.
 860          */
 861         timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
 862         i2c_pxa_stop_message(i2c);
 863 
 864         /*
 865          * We place the return code in i2c->msg_idx.
 866          */
 867         ret = i2c->msg_idx;
 868 
 869         if (!timeout && i2c->msg_num) {
 870                 i2c_pxa_scream_blue_murder(i2c, "timeout");
 871                 ret = I2C_RETRY;
 872         }
 873 
 874  out:
 875         return ret;
 876 }
 877 
 878 static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
 879                             struct i2c_msg msgs[], int num)
 880 {
 881         struct pxa_i2c *i2c = adap->algo_data;
 882         int ret, i;
 883 
 884         /* If the I2C controller is disabled we need to reset it
 885           (probably due to a suspend/resume destroying state). We do
 886           this here as we can then avoid worrying about resuming the
 887           controller before its users. */
 888         if (!(readl(_ICR(i2c)) & ICR_IUE))
 889                 i2c_pxa_reset(i2c);
 890 
 891         for (i = adap->retries; i >= 0; i--) {
 892                 ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
 893                 if (ret != I2C_RETRY)
 894                         goto out;
 895 
 896                 if (i2c_debug)
 897                         dev_dbg(&adap->dev, "Retrying transmission\n");
 898                 udelay(100);
 899         }
 900         i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
 901         ret = -EREMOTEIO;
 902  out:
 903         i2c_pxa_set_slave(i2c, ret);
 904         return ret;
 905 }
 906 
 907 /*
 908  * i2c_pxa_master_complete - complete the message and wake up.
 909  */
 910 static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret)
 911 {
 912         i2c->msg_ptr = 0;
 913         i2c->msg = NULL;
 914         i2c->msg_idx ++;
 915         i2c->msg_num = 0;
 916         if (ret)
 917                 i2c->msg_idx = ret;
 918         if (!i2c->use_pio)
 919                 wake_up(&i2c->wait);
 920 }
 921 
 922 static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
 923 {
 924         u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
 925 
 926  again:
 927         /*
 928          * If ISR_ALD is set, we lost arbitration.
 929          */
 930         if (isr & ISR_ALD) {
 931                 /*
 932                  * Do we need to do anything here?  The PXA docs
 933                  * are vague about what happens.
 934                  */
 935                 i2c_pxa_scream_blue_murder(i2c, "ALD set");
 936 
 937                 /*
 938                  * We ignore this error.  We seem to see spurious ALDs
 939                  * for seemingly no reason.  If we handle them as I think
 940                  * they should, we end up causing an I2C error, which
 941                  * is painful for some systems.
 942                  */
 943                 return; /* ignore */
 944         }
 945 
 946         if ((isr & ISR_BED) &&
 947                 (!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
 948                         (isr & ISR_ACKNAK)))) {
 949                 int ret = BUS_ERROR;
 950 
 951                 /*
 952                  * I2C bus error - either the device NAK'd us, or
 953                  * something more serious happened.  If we were NAK'd
 954                  * on the initial address phase, we can retry.
 955                  */
 956                 if (isr & ISR_ACKNAK) {
 957                         if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
 958                                 ret = I2C_RETRY;
 959                         else
 960                                 ret = XFER_NAKED;
 961                 }
 962                 i2c_pxa_master_complete(i2c, ret);
 963         } else if (isr & ISR_RWM) {
 964                 /*
 965                  * Read mode.  We have just sent the address byte, and
 966                  * now we must initiate the transfer.
 967                  */
 968                 if (i2c->msg_ptr == i2c->msg->len - 1 &&
 969                     i2c->msg_idx == i2c->msg_num - 1)
 970                         icr |= ICR_STOP | ICR_ACKNAK;
 971 
 972                 icr |= ICR_ALDIE | ICR_TB;
 973         } else if (i2c->msg_ptr < i2c->msg->len) {
 974                 /*
 975                  * Write mode.  Write the next data byte.
 976                  */
 977                 writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c));
 978 
 979                 icr |= ICR_ALDIE | ICR_TB;
 980 
 981                 /*
 982                  * If this is the last byte of the last message or last byte
 983                  * of any message with I2C_M_STOP (e.g. SCCB), send a STOP.
 984                  */
 985                 if ((i2c->msg_ptr == i2c->msg->len) &&
 986                         ((i2c->msg->flags & I2C_M_STOP) ||
 987                         (i2c->msg_idx == i2c->msg_num - 1)))
 988                                 icr |= ICR_STOP;
 989 
 990         } else if (i2c->msg_idx < i2c->msg_num - 1) {
 991                 /*
 992                  * Next segment of the message.
 993                  */
 994                 i2c->msg_ptr = 0;
 995                 i2c->msg_idx ++;
 996                 i2c->msg++;
 997 
 998                 /*
 999                  * If we aren't doing a repeated start and address,
1000                  * go back and try to send the next byte.  Note that
1001                  * we do not support switching the R/W direction here.
1002                  */
1003                 if (i2c->msg->flags & I2C_M_NOSTART)
1004                         goto again;
1005 
1006                 /*
1007                  * Write the next address.
1008                  */
1009                 writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
1010                 i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
1011 
1012                 /*
1013                  * And trigger a repeated start, and send the byte.
1014                  */
1015                 icr &= ~ICR_ALDIE;
1016                 icr |= ICR_START | ICR_TB;
1017         } else {
1018                 if (i2c->msg->len == 0) {
1019                         /*
1020                          * Device probes have a message length of zero
1021                          * and need the bus to be reset before it can
1022                          * be used again.
1023                          */
1024                         i2c_pxa_reset(i2c);
1025                 }
1026                 i2c_pxa_master_complete(i2c, 0);
1027         }
1028 
1029         i2c->icrlog[i2c->irqlogidx-1] = icr;
1030 
1031         writel(icr, _ICR(i2c));
1032         show_state(i2c);
1033 }
1034 
1035 static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
1036 {
1037         u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
1038 
1039         /*
1040          * Read the byte.
1041          */
1042         i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c));
1043 
1044         if (i2c->msg_ptr < i2c->msg->len) {
1045                 /*
1046                  * If this is the last byte of the last
1047                  * message, send a STOP.
1048                  */
1049                 if (i2c->msg_ptr == i2c->msg->len - 1)
1050                         icr |= ICR_STOP | ICR_ACKNAK;
1051 
1052                 icr |= ICR_ALDIE | ICR_TB;
1053         } else {
1054                 i2c_pxa_master_complete(i2c, 0);
1055         }
1056 
1057         i2c->icrlog[i2c->irqlogidx-1] = icr;
1058 
1059         writel(icr, _ICR(i2c));
1060 }
1061 
1062 #define VALID_INT_SOURCE        (ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
1063                                 ISR_SAD | ISR_BED)
1064 static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
1065 {
1066         struct pxa_i2c *i2c = dev_id;
1067         u32 isr = readl(_ISR(i2c));
1068 
1069         if (!(isr & VALID_INT_SOURCE))
1070                 return IRQ_NONE;
1071 
1072         if (i2c_debug > 2 && 0) {
1073                 dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
1074                         __func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
1075                 decode_ISR(isr);
1076         }
1077 
1078         if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog))
1079                 i2c->isrlog[i2c->irqlogidx++] = isr;
1080 
1081         show_state(i2c);
1082 
1083         /*
1084          * Always clear all pending IRQs.
1085          */
1086         writel(isr & VALID_INT_SOURCE, _ISR(i2c));
1087 
1088         if (isr & ISR_SAD)
1089                 i2c_pxa_slave_start(i2c, isr);
1090         if (isr & ISR_SSD)
1091                 i2c_pxa_slave_stop(i2c);
1092 
1093         if (i2c_pxa_is_slavemode(i2c)) {
1094                 if (isr & ISR_ITE)
1095                         i2c_pxa_slave_txempty(i2c, isr);
1096                 if (isr & ISR_IRF)
1097                         i2c_pxa_slave_rxfull(i2c, isr);
1098         } else if (i2c->msg && (!i2c->highmode_enter)) {
1099                 if (isr & ISR_ITE)
1100                         i2c_pxa_irq_txempty(i2c, isr);
1101                 if (isr & ISR_IRF)
1102                         i2c_pxa_irq_rxfull(i2c, isr);
1103         } else if ((isr & ISR_ITE) && i2c->highmode_enter) {
1104                 i2c->highmode_enter = false;
1105                 wake_up(&i2c->wait);
1106         } else {
1107                 i2c_pxa_scream_blue_murder(i2c, "spurious irq");
1108         }
1109 
1110         return IRQ_HANDLED;
1111 }
1112 
1113 
1114 static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
1115 {
1116         struct pxa_i2c *i2c = adap->algo_data;
1117         int ret, i;
1118 
1119         for (i = adap->retries; i >= 0; i--) {
1120                 ret = i2c_pxa_do_xfer(i2c, msgs, num);
1121                 if (ret != I2C_RETRY)
1122                         goto out;
1123 
1124                 if (i2c_debug)
1125                         dev_dbg(&adap->dev, "Retrying transmission\n");
1126                 udelay(100);
1127         }
1128         i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
1129         ret = -EREMOTEIO;
1130  out:
1131         i2c_pxa_set_slave(i2c, ret);
1132         return ret;
1133 }
1134 
1135 static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
1136 {
1137         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
1138                 I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
1139 }
1140 
1141 static const struct i2c_algorithm i2c_pxa_algorithm = {
1142         .master_xfer    = i2c_pxa_xfer,
1143         .functionality  = i2c_pxa_functionality,
1144 };
1145 
1146 static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
1147         .master_xfer    = i2c_pxa_pio_xfer,
1148         .functionality  = i2c_pxa_functionality,
1149 };
1150 
1151 static const struct of_device_id i2c_pxa_dt_ids[] = {
1152         { .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
1153         { .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
1154         { .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
1155         { .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
1156         {}
1157 };
1158 MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
1159 
1160 static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
1161                             enum pxa_i2c_types *i2c_types)
1162 {
1163         struct device_node *np = pdev->dev.of_node;
1164         const struct of_device_id *of_id =
1165                         of_match_device(i2c_pxa_dt_ids, &pdev->dev);
1166 
1167         if (!of_id)
1168                 return 1;
1169 
1170         /* For device tree we always use the dynamic or alias-assigned ID */
1171         i2c->adap.nr = -1;
1172 
1173         if (of_get_property(np, "mrvl,i2c-polling", NULL))
1174                 i2c->use_pio = 1;
1175         if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
1176                 i2c->fast_mode = 1;
1177 
1178         *i2c_types = (enum pxa_i2c_types)(of_id->data);
1179 
1180         return 0;
1181 }
1182 
1183 static int i2c_pxa_probe_pdata(struct platform_device *pdev,
1184                                struct pxa_i2c *i2c,
1185                                enum pxa_i2c_types *i2c_types)
1186 {
1187         struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
1188         const struct platform_device_id *id = platform_get_device_id(pdev);
1189 
1190         *i2c_types = id->driver_data;
1191         if (plat) {
1192                 i2c->use_pio = plat->use_pio;
1193                 i2c->fast_mode = plat->fast_mode;
1194                 i2c->high_mode = plat->high_mode;
1195                 i2c->master_code = plat->master_code;
1196                 if (!i2c->master_code)
1197                         i2c->master_code = 0xe;
1198                 i2c->rate = plat->rate;
1199         }
1200         return 0;
1201 }
1202 
1203 static int i2c_pxa_probe(struct platform_device *dev)
1204 {
1205         struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
1206         enum pxa_i2c_types i2c_type;
1207         struct pxa_i2c *i2c;
1208         struct resource *res = NULL;
1209         int ret, irq;
1210 
1211         i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
1212         if (!i2c)
1213                 return -ENOMEM;
1214 
1215         res = platform_get_resource(dev, IORESOURCE_MEM, 0);
1216         i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
1217         if (IS_ERR(i2c->reg_base))
1218                 return PTR_ERR(i2c->reg_base);
1219 
1220         irq = platform_get_irq(dev, 0);
1221         if (irq < 0) {
1222                 dev_err(&dev->dev, "no irq resource: %d\n", irq);
1223                 return irq;
1224         }
1225 
1226         /* Default adapter num to device id; i2c_pxa_probe_dt can override. */
1227         i2c->adap.nr = dev->id;
1228 
1229         ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
1230         if (ret > 0)
1231                 ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
1232         if (ret < 0)
1233                 return ret;
1234 
1235         i2c->adap.owner   = THIS_MODULE;
1236         i2c->adap.retries = 5;
1237 
1238         spin_lock_init(&i2c->lock);
1239         init_waitqueue_head(&i2c->wait);
1240 
1241         strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
1242 
1243         i2c->clk = devm_clk_get(&dev->dev, NULL);
1244         if (IS_ERR(i2c->clk)) {
1245                 dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
1246                 return PTR_ERR(i2c->clk);
1247         }
1248 
1249         i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
1250         i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
1251         i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
1252         i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
1253         i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
1254         i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
1255 
1256         if (i2c_type != REGS_CE4100)
1257                 i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
1258 
1259         if (i2c_type == REGS_PXA910) {
1260                 i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
1261                 i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
1262         }
1263 
1264         i2c->iobase = res->start;
1265         i2c->iosize = resource_size(res);
1266 
1267         i2c->irq = irq;
1268 
1269         i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
1270         i2c->highmode_enter = false;
1271 
1272         if (plat) {
1273 #ifdef CONFIG_I2C_PXA_SLAVE
1274                 i2c->slave_addr = plat->slave_addr;
1275                 i2c->slave = plat->slave;
1276 #endif
1277                 i2c->adap.class = plat->class;
1278         }
1279 
1280         if (i2c->high_mode) {
1281                 if (i2c->rate) {
1282                         clk_set_rate(i2c->clk, i2c->rate);
1283                         pr_info("i2c: <%s> set rate to %ld\n",
1284                                 i2c->adap.name, clk_get_rate(i2c->clk));
1285                 } else
1286                         pr_warn("i2c: <%s> clock rate not set\n",
1287                                 i2c->adap.name);
1288         }
1289 
1290         clk_prepare_enable(i2c->clk);
1291 
1292         if (i2c->use_pio) {
1293                 i2c->adap.algo = &i2c_pxa_pio_algorithm;
1294         } else {
1295                 i2c->adap.algo = &i2c_pxa_algorithm;
1296                 ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
1297                                 IRQF_SHARED | IRQF_NO_SUSPEND,
1298                                 dev_name(&dev->dev), i2c);
1299                 if (ret) {
1300                         dev_err(&dev->dev, "failed to request irq: %d\n", ret);
1301                         goto ereqirq;
1302                 }
1303         }
1304 
1305         i2c_pxa_reset(i2c);
1306 
1307         i2c->adap.algo_data = i2c;
1308         i2c->adap.dev.parent = &dev->dev;
1309 #ifdef CONFIG_OF
1310         i2c->adap.dev.of_node = dev->dev.of_node;
1311 #endif
1312 
1313         ret = i2c_add_numbered_adapter(&i2c->adap);
1314         if (ret < 0)
1315                 goto ereqirq;
1316 
1317         platform_set_drvdata(dev, i2c);
1318 
1319 #ifdef CONFIG_I2C_PXA_SLAVE
1320         dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
1321                 i2c->slave_addr);
1322 #else
1323         dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
1324 #endif
1325         return 0;
1326 
1327 ereqirq:
1328         clk_disable_unprepare(i2c->clk);
1329         return ret;
1330 }
1331 
1332 static int i2c_pxa_remove(struct platform_device *dev)
1333 {
1334         struct pxa_i2c *i2c = platform_get_drvdata(dev);
1335 
1336         i2c_del_adapter(&i2c->adap);
1337 
1338         clk_disable_unprepare(i2c->clk);
1339 
1340         return 0;
1341 }
1342 
1343 #ifdef CONFIG_PM
1344 static int i2c_pxa_suspend_noirq(struct device *dev)
1345 {
1346         struct pxa_i2c *i2c = dev_get_drvdata(dev);
1347 
1348         clk_disable(i2c->clk);
1349 
1350         return 0;
1351 }
1352 
1353 static int i2c_pxa_resume_noirq(struct device *dev)
1354 {
1355         struct pxa_i2c *i2c = dev_get_drvdata(dev);
1356 
1357         clk_enable(i2c->clk);
1358         i2c_pxa_reset(i2c);
1359 
1360         return 0;
1361 }
1362 
1363 static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
1364         .suspend_noirq = i2c_pxa_suspend_noirq,
1365         .resume_noirq = i2c_pxa_resume_noirq,
1366 };
1367 
1368 #define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
1369 #else
1370 #define I2C_PXA_DEV_PM_OPS NULL
1371 #endif
1372 
1373 static struct platform_driver i2c_pxa_driver = {
1374         .probe          = i2c_pxa_probe,
1375         .remove         = i2c_pxa_remove,
1376         .driver         = {
1377                 .name   = "pxa2xx-i2c",
1378                 .pm     = I2C_PXA_DEV_PM_OPS,
1379                 .of_match_table = i2c_pxa_dt_ids,
1380         },
1381         .id_table       = i2c_pxa_id_table,
1382 };
1383 
1384 static int __init i2c_adap_pxa_init(void)
1385 {
1386         return platform_driver_register(&i2c_pxa_driver);
1387 }
1388 
1389 static void __exit i2c_adap_pxa_exit(void)
1390 {
1391         platform_driver_unregister(&i2c_pxa_driver);
1392 }
1393 
1394 MODULE_LICENSE("GPL");
1395 MODULE_ALIAS("platform:pxa2xx-i2c");
1396 
1397 subsys_initcall(i2c_adap_pxa_init);
1398 module_exit(i2c_adap_pxa_exit);
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/i2c/busses/i2c-pxa.c

DEFINITIONS
