drivers/mfd/atmel-hlcdc.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2014 Free Electrons
   4  * Copyright (C) 2014 Atmel
   5  *
   6  * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
   7  */
   8
   9 #include <linux/clk.h>
  10 #include <linux/iopoll.h>
  11 #include <linux/mfd/atmel-hlcdc.h>
  12 #include <linux/mfd/core.h>
  13 #include <linux/module.h>
  14 #include <linux/mod_devicetable.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/regmap.h>
  17
  18 #define ATMEL_HLCDC_REG_MAX             (0x4000 - 0x4)
  19
  20 struct atmel_hlcdc_regmap {
  21         void __iomem *regs;
  22 };
  23
  24 static const struct mfd_cell atmel_hlcdc_cells[] = {
  25         {
  26                 .name = "atmel-hlcdc-pwm",
  27                 .of_compatible = "atmel,hlcdc-pwm",
  28         },
  29         {
  30                 .name = "atmel-hlcdc-dc",
  31                 .of_compatible = "atmel,hlcdc-display-controller",
  32         },
  33 };
  34
  35 static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
  36                                         unsigned int val)
  37 {
  38         struct atmel_hlcdc_regmap *hregmap = context;
  39
  40         if (reg <= ATMEL_HLCDC_DIS) {
  41                 u32 status;
  42
  43                 readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
  44                                           status, !(status & ATMEL_HLCDC_SIP),
  45                                           1, 100);
  46         }
  47
  48         writel(val, hregmap->regs + reg);
  49
  50         return 0;
  51 }
  52
  53 static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
  54                                        unsigned int *val)
  55 {
  56         struct atmel_hlcdc_regmap *hregmap = context;
  57
  58         *val = readl(hregmap->regs + reg);
  59
  60         return 0;
  61 }
  62
  63 static const struct regmap_config atmel_hlcdc_regmap_config = {
  64         .reg_bits = 32,
  65         .val_bits = 32,
  66         .reg_stride = 4,
  67         .max_register = ATMEL_HLCDC_REG_MAX,
  68         .reg_write = regmap_atmel_hlcdc_reg_write,
  69         .reg_read = regmap_atmel_hlcdc_reg_read,
  70         .fast_io = true,
  71 };
  72
  73 static int atmel_hlcdc_probe(struct platform_device *pdev)
  74 {
  75         struct atmel_hlcdc_regmap *hregmap;
  76         struct device *dev = &pdev->dev;
  77         struct atmel_hlcdc *hlcdc;
  78         struct resource *res;
  79
  80         hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
  81         if (!hregmap)
  82                 return -ENOMEM;
  83
  84         hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
  85         if (!hlcdc)
  86                 return -ENOMEM;
  87
  88         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  89         hregmap->regs = devm_ioremap_resource(dev, res);
  90         if (IS_ERR(hregmap->regs))
  91                 return PTR_ERR(hregmap->regs);
  92
  93         hlcdc->irq = platform_get_irq(pdev, 0);
  94         if (hlcdc->irq < 0)
  95                 return hlcdc->irq;
  96
  97         hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
  98         if (IS_ERR(hlcdc->periph_clk)) {
  99                 dev_err(dev, "failed to get peripheral clock\n");
 100                 return PTR_ERR(hlcdc->periph_clk);
 101         }
 102
 103         hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
 104         if (IS_ERR(hlcdc->sys_clk)) {
 105                 dev_err(dev, "failed to get system clock\n");
 106                 return PTR_ERR(hlcdc->sys_clk);
 107         }
 108
 109         hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
 110         if (IS_ERR(hlcdc->slow_clk)) {
 111                 dev_err(dev, "failed to get slow clock\n");
 112                 return PTR_ERR(hlcdc->slow_clk);
 113         }
 114
 115         hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
 116                                          &atmel_hlcdc_regmap_config);
 117         if (IS_ERR(hlcdc->regmap))
 118                 return PTR_ERR(hlcdc->regmap);
 119
 120         dev_set_drvdata(dev, hlcdc);
 121
 122         return devm_mfd_add_devices(dev, -1, atmel_hlcdc_cells,
 123                                     ARRAY_SIZE(atmel_hlcdc_cells),
 124                                     NULL, 0, NULL);
 125 }
 126
 127 static const struct of_device_id atmel_hlcdc_match[] = {
 128         { .compatible = "atmel,at91sam9n12-hlcdc" },
 129         { .compatible = "atmel,at91sam9x5-hlcdc" },
 130         { .compatible = "atmel,sama5d2-hlcdc" },
 131         { .compatible = "atmel,sama5d3-hlcdc" },
 132         { .compatible = "atmel,sama5d4-hlcdc" },
 133         { .compatible = "microchip,sam9x60-hlcdc" },
 134         { /* sentinel */ },
 135 };
 136 MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);
 137
 138 static struct platform_driver atmel_hlcdc_driver = {
 139         .probe = atmel_hlcdc_probe,
 140         .driver = {
 141                 .name = "atmel-hlcdc",
 142                 .of_match_table = atmel_hlcdc_match,
 143         },
 144 };
 145 module_platform_driver(atmel_hlcdc_driver);
 146
 147 MODULE_ALIAS("platform:atmel-hlcdc");
 148 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
 149 MODULE_DESCRIPTION("Atmel HLCDC driver");
 150 MODULE_LICENSE("GPL v2");