drivers/mfd/pm8921-core.c

   1 /*
   2  * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 and
   6  * only version 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #define pr_fmt(fmt) "%s: " fmt, __func__
  15
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/slab.h>
  20 #include <linux/err.h>
  21 #include <linux/ssbi.h>
  22 #include <linux/mfd/core.h>
  23 #include <linux/mfd/pm8xxx/pm8921.h>
  24 #include <linux/mfd/pm8xxx/core.h>
  25
  26 #define REG_HWREV               0x002  /* PMIC4 revision */
  27 #define REG_HWREV_2             0x0E8  /* PMIC4 revision 2 */
  28
  29 struct pm8921 {
  30         struct device                   *dev;
  31         struct pm_irq_chip              *irq_chip;
  32 };
  33
  34 static int pm8921_readb(const struct device *dev, u16 addr, u8 *val)
  35 {
  36         const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
  37         const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
  38
  39         return ssbi_read(pmic->dev->parent, addr, val, 1);
  40 }
  41
  42 static int pm8921_writeb(const struct device *dev, u16 addr, u8 val)
  43 {
  44         const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
  45         const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
  46
  47         return ssbi_write(pmic->dev->parent, addr, &val, 1);
  48 }
  49
  50 static int pm8921_read_buf(const struct device *dev, u16 addr, u8 *buf,
  51                                                                         int cnt)
  52 {
  53         const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
  54         const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
  55
  56         return ssbi_read(pmic->dev->parent, addr, buf, cnt);
  57 }
  58
  59 static int pm8921_write_buf(const struct device *dev, u16 addr, u8 *buf,
  60                                                                         int cnt)
  61 {
  62         const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
  63         const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
  64
  65         return ssbi_write(pmic->dev->parent, addr, buf, cnt);
  66 }
  67
  68 static int pm8921_read_irq_stat(const struct device *dev, int irq)
  69 {
  70         const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);
  71         const struct pm8921 *pmic = pm8921_drvdata->pm_chip_data;
  72
  73         return pm8xxx_get_irq_stat(pmic->irq_chip, irq);
  74 }
  75
  76 static struct pm8xxx_drvdata pm8921_drvdata = {
  77         .pmic_readb             = pm8921_readb,
  78         .pmic_writeb            = pm8921_writeb,
  79         .pmic_read_buf          = pm8921_read_buf,
  80         .pmic_write_buf         = pm8921_write_buf,
  81         .pmic_read_irq_stat     = pm8921_read_irq_stat,
  82 };
  83
  84 static int pm8921_add_subdevices(const struct pm8921_platform_data
  85                                            *pdata,
  86                                            struct pm8921 *pmic,
  87                                            u32 rev)
  88 {
  89         int ret = 0, irq_base = 0;
  90         struct pm_irq_chip *irq_chip;
  91
  92         if (pdata->irq_pdata) {
  93                 pdata->irq_pdata->irq_cdata.nirqs = PM8921_NR_IRQS;
  94                 pdata->irq_pdata->irq_cdata.rev = rev;
  95                 irq_base = pdata->irq_pdata->irq_base;
  96                 irq_chip = pm8xxx_irq_init(pmic->dev, pdata->irq_pdata);
  97
  98                 if (IS_ERR(irq_chip)) {
  99                         pr_err("Failed to init interrupts ret=%ld\n",
 100                                         PTR_ERR(irq_chip));
 101                         return PTR_ERR(irq_chip);
 102                 }
 103                 pmic->irq_chip = irq_chip;
 104         }
 105         return ret;
 106 }
 107
 108 static int pm8921_probe(struct platform_device *pdev)
 109 {
 110         const struct pm8921_platform_data *pdata = dev_get_platdata(&pdev->dev);
 111         struct pm8921 *pmic;
 112         int rc;
 113         u8 val;
 114         u32 rev;
 115
 116         if (!pdata) {
 117                 pr_err("missing platform data\n");
 118                 return -EINVAL;
 119         }
 120
 121         pmic = devm_kzalloc(&pdev->dev, sizeof(struct pm8921), GFP_KERNEL);
 122         if (!pmic) {
 123                 pr_err("Cannot alloc pm8921 struct\n");
 124                 return -ENOMEM;
 125         }
 126
 127         /* Read PMIC chip revision */
 128         rc = ssbi_read(pdev->dev.parent, REG_HWREV, &val, sizeof(val));
 129         if (rc) {
 130                 pr_err("Failed to read hw rev reg %d:rc=%d\n", REG_HWREV, rc);
 131                 return rc;
 132         }
 133         pr_info("PMIC revision 1: %02X\n", val);
 134         rev = val;
 135
 136         /* Read PMIC chip revision 2 */
 137         rc = ssbi_read(pdev->dev.parent, REG_HWREV_2, &val, sizeof(val));
 138         if (rc) {
 139                 pr_err("Failed to read hw rev 2 reg %d:rc=%d\n",
 140                         REG_HWREV_2, rc);
 141                 return rc;
 142         }
 143         pr_info("PMIC revision 2: %02X\n", val);
 144         rev |= val << BITS_PER_BYTE;
 145
 146         pmic->dev = &pdev->dev;
 147         pm8921_drvdata.pm_chip_data = pmic;
 148         platform_set_drvdata(pdev, &pm8921_drvdata);
 149
 150         rc = pm8921_add_subdevices(pdata, pmic, rev);
 151         if (rc) {
 152                 pr_err("Cannot add subdevices rc=%d\n", rc);
 153                 goto err;
 154         }
 155
 156         /* gpio might not work if no irq device is found */
 157         WARN_ON(pmic->irq_chip == NULL);
 158
 159         return 0;
 160
 161 err:
 162         mfd_remove_devices(pmic->dev);
 163         return rc;
 164 }
 165
 166 static int pm8921_remove(struct platform_device *pdev)
 167 {
 168         struct pm8xxx_drvdata *drvdata;
 169         struct pm8921 *pmic = NULL;
 170
 171         drvdata = platform_get_drvdata(pdev);
 172         if (drvdata)
 173                 pmic = drvdata->pm_chip_data;
 174         if (pmic)
 175                 mfd_remove_devices(pmic->dev);
 176         if (pmic->irq_chip) {
 177                 pm8xxx_irq_exit(pmic->irq_chip);
 178                 pmic->irq_chip = NULL;
 179         }
 180
 181         return 0;
 182 }
 183
 184 static struct platform_driver pm8921_driver = {
 185         .probe          = pm8921_probe,
 186         .remove         = pm8921_remove,
 187         .driver         = {
 188                 .name   = "pm8921-core",
 189                 .owner  = THIS_MODULE,
 190         },
 191 };
 192
 193 static int __init pm8921_init(void)
 194 {
 195         return platform_driver_register(&pm8921_driver);
 196 }
 197 subsys_initcall(pm8921_init);
 198
 199 static void __exit pm8921_exit(void)
 200 {
 201         platform_driver_unregister(&pm8921_driver);
 202 }
 203 module_exit(pm8921_exit);
 204
 205 MODULE_LICENSE("GPL v2");
 206 MODULE_DESCRIPTION("PMIC 8921 core driver");
 207 MODULE_VERSION("1.0");
 208 MODULE_ALIAS("platform:pm8921-core");