drivers/mfd/mxs-lradc.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003  * Freescale MXS Low Resolution Analog-to-Digital Converter driver
0004  *
0005  * Copyright (c) 2012 DENX Software Engineering, GmbH.
0006  * Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
0007  *
0008  * Authors:
0009  *  Marek Vasut <marex@denx.de>
0010  *  Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
0011  */
0012
0013 #include <linux/clk.h>
0014 #include <linux/device.h>
0015 #include <linux/mfd/core.h>
0016 #include <linux/mfd/mxs-lradc.h>
0017 #include <linux/module.h>
0018 #include <linux/of.h>
0019 #include <linux/of_device.h>
0020 #include <linux/platform_device.h>
0021 #include <linux/slab.h>
0022
0023 #define ADC_CELL        0
0024 #define TSC_CELL        1
0025 #define RES_MEM         0
0026
0027 enum mx23_lradc_irqs {
0028     MX23_LRADC_TS_IRQ = 0,
0029     MX23_LRADC_CH0_IRQ,
0030     MX23_LRADC_CH1_IRQ,
0031     MX23_LRADC_CH2_IRQ,
0032     MX23_LRADC_CH3_IRQ,
0033     MX23_LRADC_CH4_IRQ,
0034     MX23_LRADC_CH5_IRQ,
0035     MX23_LRADC_CH6_IRQ,
0036     MX23_LRADC_CH7_IRQ,
0037 };
0038
0039 enum mx28_lradc_irqs {
0040     MX28_LRADC_TS_IRQ = 0,
0041     MX28_LRADC_TRESH0_IRQ,
0042     MX28_LRADC_TRESH1_IRQ,
0043     MX28_LRADC_CH0_IRQ,
0044     MX28_LRADC_CH1_IRQ,
0045     MX28_LRADC_CH2_IRQ,
0046     MX28_LRADC_CH3_IRQ,
0047     MX28_LRADC_CH4_IRQ,
0048     MX28_LRADC_CH5_IRQ,
0049     MX28_LRADC_CH6_IRQ,
0050     MX28_LRADC_CH7_IRQ,
0051     MX28_LRADC_BUTTON0_IRQ,
0052     MX28_LRADC_BUTTON1_IRQ,
0053 };
0054
0055 static struct resource mx23_adc_resources[] = {
0056     DEFINE_RES_MEM(0x0, 0x0),
0057     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
0058     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
0059     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
0060     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
0061     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
0062     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
0063 };
0064
0065 static struct resource mx23_touchscreen_resources[] = {
0066     DEFINE_RES_MEM(0x0, 0x0),
0067     DEFINE_RES_IRQ_NAMED(MX23_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
0068     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
0069     DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
0070 };
0071
0072 static struct resource mx28_adc_resources[] = {
0073     DEFINE_RES_MEM(0x0, 0x0),
0074     DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH0_IRQ, "mxs-lradc-thresh0"),
0075     DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH1_IRQ, "mxs-lradc-thresh1"),
0076     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
0077     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
0078     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
0079     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
0080     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
0081     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
0082     DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON0_IRQ, "mxs-lradc-button0"),
0083     DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON1_IRQ, "mxs-lradc-button1"),
0084 };
0085
0086 static struct resource mx28_touchscreen_resources[] = {
0087     DEFINE_RES_MEM(0x0, 0x0),
0088     DEFINE_RES_IRQ_NAMED(MX28_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
0089     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
0090     DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
0091 };
0092
0093 static struct mfd_cell mx23_cells[] = {
0094     {
0095         .name = "mxs-lradc-adc",
0096         .resources = mx23_adc_resources,
0097         .num_resources = ARRAY_SIZE(mx23_adc_resources),
0098     },
0099     {
0100         .name = "mxs-lradc-ts",
0101         .resources = mx23_touchscreen_resources,
0102         .num_resources = ARRAY_SIZE(mx23_touchscreen_resources),
0103     },
0104 };
0105
0106 static struct mfd_cell mx28_cells[] = {
0107     {
0108         .name = "mxs-lradc-adc",
0109         .resources = mx28_adc_resources,
0110         .num_resources = ARRAY_SIZE(mx28_adc_resources),
0111     },
0112     {
0113         .name = "mxs-lradc-ts",
0114         .resources = mx28_touchscreen_resources,
0115         .num_resources = ARRAY_SIZE(mx28_touchscreen_resources),
0116     }
0117 };
0118
0119 static const struct of_device_id mxs_lradc_dt_ids[] = {
0120     { .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
0121     { .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
0122     { /* sentinel */ }
0123 };
0124 MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
0125
0126 static int mxs_lradc_probe(struct platform_device *pdev)
0127 {
0128     const struct of_device_id *of_id;
0129     struct device *dev = &pdev->dev;
0130     struct device_node *node = dev->of_node;
0131     struct mxs_lradc *lradc;
0132     struct mfd_cell *cells = NULL;
0133     struct resource *res;
0134     int ret = 0;
0135     u32 ts_wires = 0;
0136
0137     lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
0138     if (!lradc)
0139         return -ENOMEM;
0140
0141     of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
0142     if (!of_id)
0143         return -EINVAL;
0144
0145     lradc->soc = (enum mxs_lradc_id)of_id->data;
0146
0147     lradc->clk = devm_clk_get(&pdev->dev, NULL);
0148     if (IS_ERR(lradc->clk)) {
0149         dev_err(dev, "Failed to get the delay unit clock\n");
0150         return PTR_ERR(lradc->clk);
0151     }
0152
0153     ret = clk_prepare_enable(lradc->clk);
0154     if (ret) {
0155         dev_err(dev, "Failed to enable the delay unit clock\n");
0156         return ret;
0157     }
0158
0159     ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
0160                      &ts_wires);
0161
0162     if (!ret) {
0163         lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
0164
0165         switch (ts_wires) {
0166         case 4:
0167             lradc->touchscreen_wire = MXS_LRADC_TOUCHSCREEN_4WIRE;
0168             break;
0169         case 5:
0170             if (lradc->soc == IMX28_LRADC) {
0171                 lradc->touchscreen_wire =
0172                     MXS_LRADC_TOUCHSCREEN_5WIRE;
0173                 break;
0174             }
0175             fallthrough;    /* to an error message for i.MX23 */
0176         default:
0177             dev_err(&pdev->dev,
0178                 "Unsupported number of touchscreen wires (%d)\n"
0179                 , ts_wires);
0180             ret = -EINVAL;
0181             goto err_clk;
0182         }
0183     } else {
0184         lradc->buffer_vchans = BUFFER_VCHANS_ALL;
0185     }
0186
0187     platform_set_drvdata(pdev, lradc);
0188
0189     res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
0190     if (!res) {
0191         ret = -ENOMEM;
0192         goto err_clk;
0193     }
0194
0195     switch (lradc->soc) {
0196     case IMX23_LRADC:
0197         mx23_adc_resources[RES_MEM] = *res;
0198         mx23_touchscreen_resources[RES_MEM] = *res;
0199         cells = mx23_cells;
0200         break;
0201     case IMX28_LRADC:
0202         mx28_adc_resources[RES_MEM] = *res;
0203         mx28_touchscreen_resources[RES_MEM] = *res;
0204         cells = mx28_cells;
0205         break;
0206     default:
0207         dev_err(dev, "Unsupported SoC\n");
0208         ret = -ENODEV;
0209         goto err_clk;
0210     }
0211
0212     ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
0213                    &cells[ADC_CELL], 1, NULL, 0, NULL);
0214     if (ret) {
0215         dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
0216         goto err_clk;
0217     }
0218
0219     if (!lradc->touchscreen_wire)
0220         return 0;
0221
0222     ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
0223                    &cells[TSC_CELL], 1, NULL, 0, NULL);
0224     if (ret) {
0225         dev_err(&pdev->dev,
0226             "Failed to add the touchscreen subdevice\n");
0227         goto err_clk;
0228     }
0229
0230     return 0;
0231
0232 err_clk:
0233     clk_disable_unprepare(lradc->clk);
0234
0235     return ret;
0236 }
0237
0238 static int mxs_lradc_remove(struct platform_device *pdev)
0239 {
0240     struct mxs_lradc *lradc = platform_get_drvdata(pdev);
0241
0242     clk_disable_unprepare(lradc->clk);
0243
0244     return 0;
0245 }
0246
0247 static struct platform_driver mxs_lradc_driver = {
0248     .driver = {
0249         .name = "mxs-lradc",
0250         .of_match_table = mxs_lradc_dt_ids,
0251     },
0252     .probe = mxs_lradc_probe,
0253     .remove = mxs_lradc_remove,
0254 };
0255 module_platform_driver(mxs_lradc_driver);
0256
0257 MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
0258 MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
0259 MODULE_LICENSE("GPL");
0260 MODULE_ALIAS("platform:mxs-lradc");