drivers/mfd/mxs-lradc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Freescale MXS Low Resolution Analog-to-Digital Converter driver
   4  *
   5  * Copyright (c) 2012 DENX Software Engineering, GmbH.
   6  * Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
   7  *
   8  * Authors:
   9  *  Marek Vasut <marex@denx.de>
  10  *  Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
  11  */
  12
  13 #include <linux/clk.h>
  14 #include <linux/device.h>
  15 #include <linux/mfd/core.h>
  16 #include <linux/mfd/mxs-lradc.h>
  17 #include <linux/module.h>
  18 #include <linux/of.h>
  19 #include <linux/of_device.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/slab.h>
  22
  23 #define ADC_CELL                0
  24 #define TSC_CELL                1
  25 #define RES_MEM                 0
  26
  27 enum mx23_lradc_irqs {
  28         MX23_LRADC_TS_IRQ = 0,
  29         MX23_LRADC_CH0_IRQ,
  30         MX23_LRADC_CH1_IRQ,
  31         MX23_LRADC_CH2_IRQ,
  32         MX23_LRADC_CH3_IRQ,
  33         MX23_LRADC_CH4_IRQ,
  34         MX23_LRADC_CH5_IRQ,
  35         MX23_LRADC_CH6_IRQ,
  36         MX23_LRADC_CH7_IRQ,
  37 };
  38
  39 enum mx28_lradc_irqs {
  40         MX28_LRADC_TS_IRQ = 0,
  41         MX28_LRADC_TRESH0_IRQ,
  42         MX28_LRADC_TRESH1_IRQ,
  43         MX28_LRADC_CH0_IRQ,
  44         MX28_LRADC_CH1_IRQ,
  45         MX28_LRADC_CH2_IRQ,
  46         MX28_LRADC_CH3_IRQ,
  47         MX28_LRADC_CH4_IRQ,
  48         MX28_LRADC_CH5_IRQ,
  49         MX28_LRADC_CH6_IRQ,
  50         MX28_LRADC_CH7_IRQ,
  51         MX28_LRADC_BUTTON0_IRQ,
  52         MX28_LRADC_BUTTON1_IRQ,
  53 };
  54
  55 static struct resource mx23_adc_resources[] = {
  56         DEFINE_RES_MEM(0x0, 0x0),
  57         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
  58         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
  59         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
  60         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
  61         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
  62         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
  63 };
  64
  65 static struct resource mx23_touchscreen_resources[] = {
  66         DEFINE_RES_MEM(0x0, 0x0),
  67         DEFINE_RES_IRQ_NAMED(MX23_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
  68         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
  69         DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
  70 };
  71
  72 static struct resource mx28_adc_resources[] = {
  73         DEFINE_RES_MEM(0x0, 0x0),
  74         DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH0_IRQ, "mxs-lradc-thresh0"),
  75         DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH1_IRQ, "mxs-lradc-thresh1"),
  76         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
  77         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
  78         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
  79         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
  80         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
  81         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
  82         DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON0_IRQ, "mxs-lradc-button0"),
  83         DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON1_IRQ, "mxs-lradc-button1"),
  84 };
  85
  86 static struct resource mx28_touchscreen_resources[] = {
  87         DEFINE_RES_MEM(0x0, 0x0),
  88         DEFINE_RES_IRQ_NAMED(MX28_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
  89         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
  90         DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
  91 };
  92
  93 static struct mfd_cell mx23_cells[] = {
  94         {
  95                 .name = "mxs-lradc-adc",
  96                 .resources = mx23_adc_resources,
  97                 .num_resources = ARRAY_SIZE(mx23_adc_resources),
  98         },
  99         {
 100                 .name = "mxs-lradc-ts",
 101                 .resources = mx23_touchscreen_resources,
 102                 .num_resources = ARRAY_SIZE(mx23_touchscreen_resources),
 103         },
 104 };
 105
 106 static struct mfd_cell mx28_cells[] = {
 107         {
 108                 .name = "mxs-lradc-adc",
 109                 .resources = mx28_adc_resources,
 110                 .num_resources = ARRAY_SIZE(mx28_adc_resources),
 111         },
 112         {
 113                 .name = "mxs-lradc-ts",
 114                 .resources = mx28_touchscreen_resources,
 115                 .num_resources = ARRAY_SIZE(mx28_touchscreen_resources),
 116         }
 117 };
 118
 119 static const struct of_device_id mxs_lradc_dt_ids[] = {
 120         { .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
 121         { .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
 122         { /* sentinel */ }
 123 };
 124 MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
 125
 126 static int mxs_lradc_probe(struct platform_device *pdev)
 127 {
 128         const struct of_device_id *of_id;
 129         struct device *dev = &pdev->dev;
 130         struct device_node *node = dev->of_node;
 131         struct mxs_lradc *lradc;
 132         struct mfd_cell *cells = NULL;
 133         struct resource *res;
 134         int ret = 0;
 135         u32 ts_wires = 0;
 136
 137         lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
 138         if (!lradc)
 139                 return -ENOMEM;
 140
 141         of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
 142         if (!of_id)
 143                 return -EINVAL;
 144
 145         lradc->soc = (enum mxs_lradc_id)of_id->data;
 146
 147         lradc->clk = devm_clk_get(&pdev->dev, NULL);
 148         if (IS_ERR(lradc->clk)) {
 149                 dev_err(dev, "Failed to get the delay unit clock\n");
 150                 return PTR_ERR(lradc->clk);
 151         }
 152
 153         ret = clk_prepare_enable(lradc->clk);
 154         if (ret) {
 155                 dev_err(dev, "Failed to enable the delay unit clock\n");
 156                 return ret;
 157         }
 158
 159         ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
 160                                          &ts_wires);
 161
 162         if (!ret) {
 163                 lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
 164
 165                 switch (ts_wires) {
 166                 case 4:
 167                         lradc->touchscreen_wire = MXS_LRADC_TOUCHSCREEN_4WIRE;
 168                         break;
 169                 case 5:
 170                         if (lradc->soc == IMX28_LRADC) {
 171                                 lradc->touchscreen_wire =
 172                                         MXS_LRADC_TOUCHSCREEN_5WIRE;
 173                                 break;
 174                         }
 175                         /* fall through - to an error message for i.MX23 */
 176                 default:
 177                         dev_err(&pdev->dev,
 178                                 "Unsupported number of touchscreen wires (%d)\n"
 179                                 , ts_wires);
 180                         ret = -EINVAL;
 181                         goto err_clk;
 182                 }
 183         } else {
 184                 lradc->buffer_vchans = BUFFER_VCHANS_ALL;
 185         }
 186
 187         platform_set_drvdata(pdev, lradc);
 188
 189         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 190         if (!res) {
 191                 ret = -ENOMEM;
 192                 goto err_clk;
 193         }
 194
 195         switch (lradc->soc) {
 196         case IMX23_LRADC:
 197                 mx23_adc_resources[RES_MEM] = *res;
 198                 mx23_touchscreen_resources[RES_MEM] = *res;
 199                 cells = mx23_cells;
 200                 break;
 201         case IMX28_LRADC:
 202                 mx28_adc_resources[RES_MEM] = *res;
 203                 mx28_touchscreen_resources[RES_MEM] = *res;
 204                 cells = mx28_cells;
 205                 break;
 206         default:
 207                 dev_err(dev, "Unsupported SoC\n");
 208                 ret = -ENODEV;
 209                 goto err_clk;
 210         }
 211
 212         ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
 213                                    &cells[ADC_CELL], 1, NULL, 0, NULL);
 214         if (ret) {
 215                 dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
 216                 goto err_clk;
 217         }
 218
 219         if (!lradc->touchscreen_wire)
 220                 return 0;
 221
 222         ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
 223                                    &cells[TSC_CELL], 1, NULL, 0, NULL);
 224         if (ret) {
 225                 dev_err(&pdev->dev,
 226                         "Failed to add the touchscreen subdevice\n");
 227                 goto err_clk;
 228         }
 229
 230         return 0;
 231
 232 err_clk:
 233         clk_disable_unprepare(lradc->clk);
 234
 235         return ret;
 236 }
 237
 238 static int mxs_lradc_remove(struct platform_device *pdev)
 239 {
 240         struct mxs_lradc *lradc = platform_get_drvdata(pdev);
 241
 242         clk_disable_unprepare(lradc->clk);
 243
 244         return 0;
 245 }
 246
 247 static struct platform_driver mxs_lradc_driver = {
 248         .driver = {
 249                 .name = "mxs-lradc",
 250                 .of_match_table = mxs_lradc_dt_ids,
 251         },
 252         .probe = mxs_lradc_probe,
 253         .remove = mxs_lradc_remove,
 254 };
 255 module_platform_driver(mxs_lradc_driver);
 256
 257 MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
 258 MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
 259 MODULE_LICENSE("GPL");
 260 MODULE_ALIAS("platform:mxs-lradc");