drivers/mfd/sun4i-gpadc.c

   1 /* ADC MFD core driver for sunxi platforms
   2  *
   3  * Copyright (c) 2016 Quentin Schulz <quentin.schulz@free-electrons.com>
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  */
   9
  10 #include <linux/interrupt.h>
  11 #include <linux/kernel.h>
  12 #include <linux/mfd/core.h>
  13 #include <linux/module.h>
  14 #include <linux/of_device.h>
  15 #include <linux/of_irq.h>
  16 #include <linux/regmap.h>
  17
  18 #include <linux/mfd/sun4i-gpadc.h>
  19
  20 #define ARCH_SUN4I_A10 0
  21 #define ARCH_SUN5I_A13 1
  22 #define ARCH_SUN6I_A31 2
  23
  24 static struct resource adc_resources[] = {
  25         DEFINE_RES_IRQ_NAMED(SUN4I_GPADC_IRQ_FIFO_DATA, "FIFO_DATA_PENDING"),
  26         DEFINE_RES_IRQ_NAMED(SUN4I_GPADC_IRQ_TEMP_DATA, "TEMP_DATA_PENDING"),
  27 };
  28
  29 static const struct regmap_irq sun4i_gpadc_regmap_irq[] = {
  30         REGMAP_IRQ_REG(SUN4I_GPADC_IRQ_FIFO_DATA, 0,
  31                        SUN4I_GPADC_INT_FIFOC_TP_DATA_IRQ_EN),
  32         REGMAP_IRQ_REG(SUN4I_GPADC_IRQ_TEMP_DATA, 0,
  33                        SUN4I_GPADC_INT_FIFOC_TEMP_IRQ_EN),
  34 };
  35
  36 static const struct regmap_irq_chip sun4i_gpadc_regmap_irq_chip = {
  37         .name = "sun4i_gpadc_irq_chip",
  38         .status_base = SUN4I_GPADC_INT_FIFOS,
  39         .ack_base = SUN4I_GPADC_INT_FIFOS,
  40         .mask_base = SUN4I_GPADC_INT_FIFOC,
  41         .init_ack_masked = true,
  42         .mask_invert = true,
  43         .irqs = sun4i_gpadc_regmap_irq,
  44         .num_irqs = ARRAY_SIZE(sun4i_gpadc_regmap_irq),
  45         .num_regs = 1,
  46 };
  47
  48 static struct mfd_cell sun4i_gpadc_cells[] = {
  49         {
  50                 .name   = "sun4i-a10-gpadc-iio",
  51                 .resources = adc_resources,
  52                 .num_resources = ARRAY_SIZE(adc_resources),
  53         },
  54         { .name = "iio_hwmon" }
  55 };
  56
  57 static struct mfd_cell sun5i_gpadc_cells[] = {
  58         {
  59                 .name   = "sun5i-a13-gpadc-iio",
  60                 .resources = adc_resources,
  61                 .num_resources = ARRAY_SIZE(adc_resources),
  62         },
  63         { .name = "iio_hwmon" },
  64 };
  65
  66 static struct mfd_cell sun6i_gpadc_cells[] = {
  67         {
  68                 .name   = "sun6i-a31-gpadc-iio",
  69                 .resources = adc_resources,
  70                 .num_resources = ARRAY_SIZE(adc_resources),
  71         },
  72         { .name = "iio_hwmon" },
  73 };
  74
  75 static const struct regmap_config sun4i_gpadc_regmap_config = {
  76         .reg_bits = 32,
  77         .val_bits = 32,
  78         .reg_stride = 4,
  79         .fast_io = true,
  80 };
  81
  82 static const struct of_device_id sun4i_gpadc_of_match[] = {
  83         {
  84                 .compatible = "allwinner,sun4i-a10-ts",
  85                 .data = (void *)ARCH_SUN4I_A10,
  86         }, {
  87                 .compatible = "allwinner,sun5i-a13-ts",
  88                 .data = (void *)ARCH_SUN5I_A13,
  89         }, {
  90                 .compatible = "allwinner,sun6i-a31-ts",
  91                 .data = (void *)ARCH_SUN6I_A31,
  92         }, { /* sentinel */ }
  93 };
  94
  95 MODULE_DEVICE_TABLE(of, sun4i_gpadc_of_match);
  96
  97 static int sun4i_gpadc_probe(struct platform_device *pdev)
  98 {
  99         struct sun4i_gpadc_dev *dev;
 100         struct resource *mem;
 101         const struct of_device_id *of_id;
 102         const struct mfd_cell *cells;
 103         unsigned int irq, size;
 104         int ret;
 105
 106         of_id = of_match_node(sun4i_gpadc_of_match, pdev->dev.of_node);
 107         if (!of_id)
 108                 return -EINVAL;
 109
 110         switch ((long)of_id->data) {
 111         case ARCH_SUN4I_A10:
 112                 cells = sun4i_gpadc_cells;
 113                 size = ARRAY_SIZE(sun4i_gpadc_cells);
 114                 break;
 115         case ARCH_SUN5I_A13:
 116                 cells = sun5i_gpadc_cells;
 117                 size = ARRAY_SIZE(sun5i_gpadc_cells);
 118                 break;
 119         case ARCH_SUN6I_A31:
 120                 cells = sun6i_gpadc_cells;
 121                 size = ARRAY_SIZE(sun6i_gpadc_cells);
 122                 break;
 123         default:
 124                 return -EINVAL;
 125         }
 126
 127         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 128         if (!dev)
 129                 return -ENOMEM;
 130
 131         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 132         dev->base = devm_ioremap_resource(&pdev->dev, mem);
 133         if (IS_ERR(dev->base))
 134                 return PTR_ERR(dev->base);
 135
 136         dev->dev = &pdev->dev;
 137         dev_set_drvdata(dev->dev, dev);
 138
 139         dev->regmap = devm_regmap_init_mmio(dev->dev, dev->base,
 140                                             &sun4i_gpadc_regmap_config);
 141         if (IS_ERR(dev->regmap)) {
 142                 ret = PTR_ERR(dev->regmap);
 143                 dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
 144                 return ret;
 145         }
 146
 147         /* Disable all interrupts */
 148         regmap_write(dev->regmap, SUN4I_GPADC_INT_FIFOC, 0);
 149
 150         irq = platform_get_irq(pdev, 0);
 151         ret = devm_regmap_add_irq_chip(&pdev->dev, dev->regmap, irq,
 152                                        IRQF_ONESHOT, 0,
 153                                        &sun4i_gpadc_regmap_irq_chip,
 154                                        &dev->regmap_irqc);
 155         if (ret) {
 156                 dev_err(&pdev->dev, "failed to add irq chip: %d\n", ret);
 157                 return ret;
 158         }
 159
 160         ret = devm_mfd_add_devices(dev->dev, 0, cells, size, NULL, 0, NULL);
 161         if (ret) {
 162                 dev_err(&pdev->dev, "failed to add MFD devices: %d\n", ret);
 163                 return ret;
 164         }
 165
 166         return 0;
 167 }
 168
 169 static struct platform_driver sun4i_gpadc_driver = {
 170         .driver = {
 171                 .name = "sun4i-gpadc",
 172                 .of_match_table = of_match_ptr(sun4i_gpadc_of_match),
 173         },
 174         .probe = sun4i_gpadc_probe,
 175 };
 176
 177 module_platform_driver(sun4i_gpadc_driver);
 178
 179 MODULE_DESCRIPTION("Allwinner sunxi platforms' GPADC MFD core driver");
 180 MODULE_AUTHOR("Quentin Schulz <quentin.schulz@free-electrons.com>");
 181 MODULE_LICENSE("GPL v2");