Quelle  ibm-cffps.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Copyright 2017 IBM Corp.
 */

#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/debugfs.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/i2c.h>
#include <linux/jiffies.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/pmbus.h>

#include "pmbus.h"

#define CFFPS_CCIN_CMD    0xBD
#define CFFPS_FW_CMD    0xFA
#define CFFPS1_FW_NUM_BYTES   4
#define CFFPS2_FW_NUM_WORDS   3
#define CFFPS_SYS_CONFIG_CMD   0xDA
#define CFFPS_12VCS_VOUT_CMD   0xDE

#define CFFPS_INPUT_HISTORY_CMD   0xD6
#define CFFPS_INPUT_HISTORY_SIZE  101

#define CFFPS_CCIN_REVISION   GENMASK(7, 0)
#define CFFPS_CCIN_REVISION_LEGACY   0xde
#define CFFPS_CCIN_VERSION   GENMASK(15, 8)
#define CFFPS_CCIN_VERSION_1    0x2b
#define CFFPS_CCIN_VERSION_2    0x2e
#define CFFPS_CCIN_VERSION_3    0x51

/* STATUS_MFR_SPECIFIC bits */
#define CFFPS_MFR_FAN_FAULT   BIT(0)
#define CFFPS_MFR_THERMAL_FAULT   BIT(1)
#define CFFPS_MFR_OV_FAULT   BIT(2)
#define CFFPS_MFR_UV_FAULT   BIT(3)
#define CFFPS_MFR_PS_KILL   BIT(4)
#define CFFPS_MFR_OC_FAULT   BIT(5)
#define CFFPS_MFR_VAUX_FAULT   BIT(6)
#define CFFPS_MFR_CURRENT_SHARE_WARNING  BIT(7)

#define CFFPS_LED_BLINK    (BIT(0) | BIT(6))
#define CFFPS_LED_ON    (BIT(1) | BIT(6))
#define CFFPS_LED_OFF    (BIT(2) | BIT(6))
#define CFFPS_BLINK_RATE_MS   250

enum {
 CFFPS_DEBUGFS_MAX_POWER_OUT = 0,
 CFFPS_DEBUGFS_CCIN,
 CFFPS_DEBUGFS_FW,
 CFFPS_DEBUGFS_ON_OFF_CONFIG,
 CFFPS_DEBUGFS_NUM_ENTRIES
};

enum versions { cffps1, cffps2, cffps_unknown };

struct ibm_cffps {
 enum versions version;
 struct i2c_client *client;

 u8 input_history[CFFPS_INPUT_HISTORY_SIZE];

 int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];

 char led_name[32];
 u8 led_state;
 struct led_classdev led;
};

#define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])

static ssize_t ibm_cffps_debugfs_read_input_history(struct file *file, char __user *buf,
          size_t count, loff_t *ppos)
{
 int rc;
 u8 cmd = CFFPS_INPUT_HISTORY_CMD;
 struct ibm_cffps *psu = file->private_data;
 struct i2c_msg msg[2] = {
  {
   .addr = psu->client->addr,
   .flags = psu->client->flags,
   .len = 1,
   .buf = &cmd,
  }, {
   .addr = psu->client->addr,
   .flags = psu->client->flags | I2C_M_RD,
   .len = CFFPS_INPUT_HISTORY_SIZE,
   .buf = psu->input_history,
  },
 };

 if (!*ppos) {
  rc = pmbus_lock_interruptible(psu->client);
  if (rc)
   return rc;

  rc = pmbus_set_page(psu->client, 0, 0xff);
  if (rc) {
   pmbus_unlock(psu->client);
   return rc;
  }

  /*
 * Use a raw i2c transfer, since we need more bytes
 * than Linux I2C supports through smbus xfr (only 32).
 */
  rc = i2c_transfer(psu->client->adapter, msg, 2);
  pmbus_unlock(psu->client);
  if (rc < 0)
   return rc;
 }

 return simple_read_from_buffer(buf, count, ppos,
           psu->input_history + 1,
           psu->input_history[0]);
}

static const struct file_operations ibm_cffps_input_history_fops = {
 .llseek = noop_llseek,
 .read = ibm_cffps_debugfs_read_input_history,
 .open = simple_open,
};

static ssize_t ibm_cffps_debugfs_read(struct file *file, char __user *buf,
          size_t count, loff_t *ppos)
{
 int i, rc;
 int *idxp = file->private_data;
 int idx = *idxp;
 struct ibm_cffps *psu = to_psu(idxp, idx);
 char data[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };

 rc = pmbus_lock_interruptible(psu->client);
 if (rc)
  return rc;

 rc = pmbus_set_page(psu->client, 0, 0xff);
 if (rc)
  goto unlock;

 switch (idx) {
 case CFFPS_DEBUGFS_MAX_POWER_OUT:
  if (psu->version == cffps1)
   rc = i2c_smbus_read_word_swapped(psu->client, PMBUS_MFR_POUT_MAX);
  else
   rc = i2c_smbus_read_word_data(psu->client, PMBUS_MFR_POUT_MAX);
  if (rc >= 0)
   rc = snprintf(data, I2C_SMBUS_BLOCK_MAX, "%d", rc);
  break;
 case CFFPS_DEBUGFS_CCIN:
  rc = i2c_smbus_read_word_swapped(psu->client, CFFPS_CCIN_CMD);
  if (rc >= 0)
   rc = snprintf(data, 5, "%04X", rc);
  break;
 case CFFPS_DEBUGFS_FW:
  switch (psu->version) {
  case cffps1:
   for (i = 0; i < CFFPS1_FW_NUM_BYTES; ++i) {
    rc = i2c_smbus_read_byte_data(psu->client, CFFPS_FW_CMD + i);
    if (rc < 0)
     goto unlock;

    snprintf(&data[i * 2], 3, "%02X", rc);
   }

   rc = i * 2;
   break;
  case cffps2:
   for (i = 0; i < CFFPS2_FW_NUM_WORDS; ++i) {
    rc = i2c_smbus_read_word_data(psu->client, CFFPS_FW_CMD + i);
    if (rc < 0)
     goto unlock;

    snprintf(&data[i * 4], 5, "%04X", rc);
   }

   rc = i * 4;
   break;
  default:
   rc = -EOPNOTSUPP;
   break;
  }
  break;
 case CFFPS_DEBUGFS_ON_OFF_CONFIG:
  rc = i2c_smbus_read_byte_data(psu->client, PMBUS_ON_OFF_CONFIG);
  if (rc >= 0)
   rc = snprintf(data, 3, "%02x", rc);
  break;
 default:
  rc = -EINVAL;
  break;
 }

unlock:
 pmbus_unlock(psu->client);
 if (rc < 0)
  return rc;

 data[rc] = '\n';
 rc += 2;

 return simple_read_from_buffer(buf, count, ppos, data, rc);
}

static ssize_t ibm_cffps_debugfs_write(struct file *file,
           const char __user *buf, size_t count,
           loff_t *ppos)
{
 u8 data;
 ssize_t rc;
 int *idxp = file->private_data;
 int idx = *idxp;
 struct ibm_cffps *psu = to_psu(idxp, idx);

 switch (idx) {
 case CFFPS_DEBUGFS_ON_OFF_CONFIG:
  rc = simple_write_to_buffer(&data, 1, ppos, buf, count);
  if (rc <= 0)
   return rc;

  rc = pmbus_lock_interruptible(psu->client);
  if (rc)
   return rc;

  rc = pmbus_set_page(psu->client, 0, 0xff);
  if (rc) {
   pmbus_unlock(psu->client);
   return rc;
  }

  rc = i2c_smbus_write_byte_data(psu->client, PMBUS_ON_OFF_CONFIG, data);
  pmbus_unlock(psu->client);
  if (rc)
   return rc;

  rc = 1;
  break;
 default:
  return -EINVAL;
 }

 return rc;
}

static const struct file_operations ibm_cffps_fops = {
 .llseek = noop_llseek,
 .read = ibm_cffps_debugfs_read,
 .write = ibm_cffps_debugfs_write,
 .open = simple_open,
};

static int ibm_cffps_read_byte_data(struct i2c_client *client, int page,
        int reg)
{
 int rc, mfr;

 switch (reg) {
 case PMBUS_STATUS_VOUT:
 case PMBUS_STATUS_IOUT:
 case PMBUS_STATUS_TEMPERATURE:
 case PMBUS_STATUS_FAN_12:
  rc = pmbus_read_byte_data(client, page, reg);
  if (rc < 0)
   return rc;

  mfr = pmbus_read_byte_data(client, page,
        PMBUS_STATUS_MFR_SPECIFIC);
  if (mfr < 0)
   /*
 * Return the status register instead of an error,
 * since we successfully read status.
 */
   return rc;

  /* Add MFR_SPECIFIC bits to the standard pmbus status regs. */
  if (reg == PMBUS_STATUS_FAN_12) {
   if (mfr & CFFPS_MFR_FAN_FAULT)
    rc |= PB_FAN_FAN1_FAULT;
  } else if (reg == PMBUS_STATUS_TEMPERATURE) {
   if (mfr & CFFPS_MFR_THERMAL_FAULT)
    rc |= PB_TEMP_OT_FAULT;
  } else if (reg == PMBUS_STATUS_VOUT) {
   if (mfr & (CFFPS_MFR_OV_FAULT | CFFPS_MFR_VAUX_FAULT))
    rc |= PB_VOLTAGE_OV_FAULT;
   if (mfr & CFFPS_MFR_UV_FAULT)
    rc |= PB_VOLTAGE_UV_FAULT;
  } else if (reg == PMBUS_STATUS_IOUT) {
   if (mfr & CFFPS_MFR_OC_FAULT)
    rc |= PB_IOUT_OC_FAULT;
   if (mfr & CFFPS_MFR_CURRENT_SHARE_WARNING)
    rc |= PB_CURRENT_SHARE_FAULT;
  }
  break;
 default:
  rc = -ENODATA;
  break;
 }

 return rc;
}

static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
        int phase, int reg)
{
 int rc, mfr;

 switch (reg) {
 case PMBUS_STATUS_WORD:
  rc = pmbus_read_word_data(client, page, phase, reg);
  if (rc < 0)
   return rc;

  mfr = pmbus_read_byte_data(client, page,
        PMBUS_STATUS_MFR_SPECIFIC);
  if (mfr < 0)
   /*
 * Return the status register instead of an error,
 * since we successfully read status.
 */
   return rc;

  if (mfr & CFFPS_MFR_PS_KILL)
   rc |= PB_STATUS_OFF;
  break;
 case PMBUS_VIRT_READ_VMON:
  rc = pmbus_read_word_data(client, page, phase,
       CFFPS_12VCS_VOUT_CMD);
  break;
 default:
  rc = -ENODATA;
  break;
 }

 return rc;
}

static int ibm_cffps_led_brightness_set(struct led_classdev *led_cdev,
     enum led_brightness brightness)
{
 int rc;
 u8 next_led_state;
 struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);

 if (brightness == LED_OFF) {
  next_led_state = CFFPS_LED_OFF;
 } else {
  brightness = LED_FULL;

  if (psu->led_state != CFFPS_LED_BLINK)
   next_led_state = CFFPS_LED_ON;
  else
   next_led_state = CFFPS_LED_BLINK;
 }

 dev_dbg(&psu->client->dev, "LED brightness set: %d. Command: %d.\n",
  brightness, next_led_state);

 rc = pmbus_lock_interruptible(psu->client);
 if (rc)
  return rc;

 rc = pmbus_set_page(psu->client, 0, 0xff);
 if (rc) {
  pmbus_unlock(psu->client);
  return rc;
 }

 rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
           next_led_state);
 pmbus_unlock(psu->client);
 if (rc < 0)
  return rc;

 psu->led_state = next_led_state;
 led_cdev->brightness = brightness;

 return 0;
}

static int ibm_cffps_led_blink_set(struct led_classdev *led_cdev,
       unsigned long *delay_on,
       unsigned long *delay_off)
{
 int rc;
 struct ibm_cffps *psu = container_of(led_cdev, struct ibm_cffps, led);

 dev_dbg(&psu->client->dev, "LED blink set.\n");

 rc = pmbus_lock_interruptible(psu->client);
 if (rc)
  return rc;

 rc = pmbus_set_page(psu->client, 0, 0xff);
 if (rc) {
  pmbus_unlock(psu->client);
  return rc;
 }

 rc = i2c_smbus_write_byte_data(psu->client, CFFPS_SYS_CONFIG_CMD,
           CFFPS_LED_BLINK);
 pmbus_unlock(psu->client);
 if (rc < 0)
  return rc;

 psu->led_state = CFFPS_LED_BLINK;
 led_cdev->brightness = LED_FULL;
 *delay_on = CFFPS_BLINK_RATE_MS;
 *delay_off = CFFPS_BLINK_RATE_MS;

 return 0;
}

static void ibm_cffps_create_led_class(struct ibm_cffps *psu)
{
 int rc;
 struct i2c_client *client = psu->client;
 struct device *dev = &client->dev;

 snprintf(psu->led_name, sizeof(psu->led_name), "%s-%02x", client->name,
   client->addr);
 psu->led.name = psu->led_name;
 psu->led.max_brightness = LED_FULL;
 psu->led.brightness_set_blocking = ibm_cffps_led_brightness_set;
 psu->led.blink_set = ibm_cffps_led_blink_set;

 rc = devm_led_classdev_register(dev, &psu->led);
 if (rc)
  dev_warn(dev, "failed to register led class: %d\n", rc);
 else
  i2c_smbus_write_byte_data(client, CFFPS_SYS_CONFIG_CMD,
       CFFPS_LED_OFF);
}

static struct pmbus_driver_info ibm_cffps_info[] = {
 [cffps1] = {
  .pages = 1,
  .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
   PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
   PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
   PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
   PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
   PMBUS_HAVE_STATUS_FAN12,
  .read_byte_data = ibm_cffps_read_byte_data,
  .read_word_data = ibm_cffps_read_word_data,
 },
 [cffps2] = {
  .pages = 2,
  .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
   PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
   PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
   PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
   PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP |
   PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_VMON,
  .func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
   PMBUS_HAVE_PIN | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 |
   PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_VOUT |
   PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT |
   PMBUS_HAVE_STATUS_TEMP,
  .read_byte_data = ibm_cffps_read_byte_data,
  .read_word_data = ibm_cffps_read_word_data,
 },
};

static struct pmbus_platform_data ibm_cffps_pdata = {
 .flags = PMBUS_SKIP_STATUS_CHECK | PMBUS_NO_CAPABILITY,
};

static const struct i2c_device_id ibm_cffps_id[] = {
 { "ibm_cffps1", cffps1 },
 { "ibm_cffps2", cffps2 },
 { "ibm_cffps", cffps_unknown },
 {}
};
MODULE_DEVICE_TABLE(i2c, ibm_cffps_id);

static int ibm_cffps_probe(struct i2c_client *client)
{
 int i, rc;
 enum versions vs = cffps_unknown;
 struct dentry *debugfs;
 struct ibm_cffps *psu;
 const void *md = of_device_get_match_data(&client->dev);
 const struct i2c_device_id *id;

 if (md) {
  vs = (uintptr_t)md;
 } else {
  id = i2c_match_id(ibm_cffps_id, client);
  if (id)
   vs = (enum versions)id->driver_data;
 }

 if (vs == cffps_unknown) {
  u16 ccin_revision = 0;
  u16 ccin_version = CFFPS_CCIN_VERSION_1;
  int ccin = i2c_smbus_read_word_swapped(client, CFFPS_CCIN_CMD);
  char mfg_id[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };

  if (ccin > 0) {
   ccin_revision = FIELD_GET(CFFPS_CCIN_REVISION, ccin);
   ccin_version = FIELD_GET(CFFPS_CCIN_VERSION, ccin);
  }

  rc = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, mfg_id);
  if (rc < 0) {
   dev_err(&client->dev, "Failed to read Manufacturer ID\n");
   return rc;
  }

  switch (ccin_version) {
  default:
  case CFFPS_CCIN_VERSION_1:
   if ((strncmp(mfg_id, "ACBE", 4) == 0) ||
         (strncmp(mfg_id, "ARTE", 4) == 0))
    vs = cffps1;
   else
    vs = cffps2;
   break;
  case CFFPS_CCIN_VERSION_2:
   vs = cffps2;
   break;
  case CFFPS_CCIN_VERSION_3:
   if (ccin_revision == CFFPS_CCIN_REVISION_LEGACY)
    vs = cffps1;
   else
    vs = cffps2;
   break;
  }

  /* Set the client name to include the version number. */
  snprintf(client->name, I2C_NAME_SIZE, "cffps%d", vs + 1);
 }

 client->dev.platform_data = &ibm_cffps_pdata;
 rc = pmbus_do_probe(client, &ibm_cffps_info[vs]);
 if (rc)
  return rc;

 /*
 * Don't fail the probe if there isn't enough memory for leds and
 * debugfs.
 */
 psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
 if (!psu)
  return 0;

 psu->version = vs;
 psu->client = client;

 ibm_cffps_create_led_class(psu);

 /* Don't fail the probe if we can't create debugfs */
 debugfs = pmbus_get_debugfs_dir(client);
 if (!debugfs)
  return 0;

 for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
  psu->debugfs_entries[i] = i;

 debugfs_create_file("input_history", 0444, debugfs, psu, &ibm_cffps_input_history_fops);
 debugfs_create_file("max_power_out", 0444, debugfs,
       &psu->debugfs_entries[CFFPS_DEBUGFS_MAX_POWER_OUT],
       &ibm_cffps_fops);
 debugfs_create_file("ccin", 0444, debugfs,
       &psu->debugfs_entries[CFFPS_DEBUGFS_CCIN],
       &ibm_cffps_fops);
 debugfs_create_file("fw_version", 0444, debugfs,
       &psu->debugfs_entries[CFFPS_DEBUGFS_FW],
       &ibm_cffps_fops);
 debugfs_create_file("on_off_config", 0644, debugfs,
       &psu->debugfs_entries[CFFPS_DEBUGFS_ON_OFF_CONFIG],
       &ibm_cffps_fops);

 /* For compatibility with users of the old naming scheme. */
 debugfs_create_symlink(client->name, debugfs, ".");

 return 0;
}

static const struct of_device_id ibm_cffps_of_match[] = {
 {
  .compatible = "ibm,cffps1",
  .data = (void *)cffps1
 },
 {
  .compatible = "ibm,cffps2",
  .data = (void *)cffps2
 },
 {
  .compatible = "ibm,cffps",
  .data = (void *)cffps_unknown
 },
 {}
};
MODULE_DEVICE_TABLE(of, ibm_cffps_of_match);

static struct i2c_driver ibm_cffps_driver = {
 .driver = {
  .name = "ibm-cffps",
  .of_match_table = ibm_cffps_of_match,
 },
 .probe = ibm_cffps_probe,
 .id_table = ibm_cffps_id,
};

module_i2c_driver(ibm_cffps_driver);

MODULE_AUTHOR("Eddie James");
MODULE_DESCRIPTION("PMBus driver for IBM Common Form Factor power supplies");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("PMBUS");