linux/drivers/input/keyboard/clps711x-keypad.c
<<
>>
Prefs
   1/*
   2 * Cirrus Logic CLPS711X Keypad driver
   3 *
   4 * Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 */
  11
  12#include <linux/input.h>
  13#include <linux/input-polldev.h>
  14#include <linux/module.h>
  15#include <linux/of_gpio.h>
  16#include <linux/platform_device.h>
  17#include <linux/regmap.h>
  18#include <linux/sched.h>
  19#include <linux/input/matrix_keypad.h>
  20#include <linux/mfd/syscon.h>
  21#include <linux/mfd/syscon/clps711x.h>
  22
  23#define CLPS711X_KEYPAD_COL_COUNT       8
  24
  25struct clps711x_gpio_data {
  26        struct gpio_desc *desc;
  27        DECLARE_BITMAP(last_state, CLPS711X_KEYPAD_COL_COUNT);
  28};
  29
  30struct clps711x_keypad_data {
  31        struct regmap                   *syscon;
  32        int                             row_count;
  33        unsigned int                    row_shift;
  34        struct clps711x_gpio_data       *gpio_data;
  35};
  36
  37static void clps711x_keypad_poll(struct input_polled_dev *dev)
  38{
  39        const unsigned short *keycodes = dev->input->keycode;
  40        struct clps711x_keypad_data *priv = dev->private;
  41        bool sync = false;
  42        int col, row;
  43
  44        for (col = 0; col < CLPS711X_KEYPAD_COL_COUNT; col++) {
  45                /* Assert column */
  46                regmap_update_bits(priv->syscon, SYSCON_OFFSET,
  47                                   SYSCON1_KBDSCAN_MASK,
  48                                   SYSCON1_KBDSCAN(8 + col));
  49
  50                /* Scan rows */
  51                for (row = 0; row < priv->row_count; row++) {
  52                        struct clps711x_gpio_data *data = &priv->gpio_data[row];
  53                        bool state, state1;
  54
  55                        /* Read twice for protection against fluctuations */
  56                        do {
  57                                state = gpiod_get_value_cansleep(data->desc);
  58                                cond_resched();
  59                                state1 = gpiod_get_value_cansleep(data->desc);
  60                        } while (state != state1);
  61
  62                        if (test_bit(col, data->last_state) != state) {
  63                                int code = MATRIX_SCAN_CODE(row, col,
  64                                                            priv->row_shift);
  65
  66                                if (state) {
  67                                        set_bit(col, data->last_state);
  68                                        input_event(dev->input, EV_MSC,
  69                                                    MSC_SCAN, code);
  70                                } else {
  71                                        clear_bit(col, data->last_state);
  72                                }
  73
  74                                if (keycodes[code])
  75                                        input_report_key(dev->input,
  76                                                         keycodes[code], state);
  77                                sync = true;
  78                        }
  79                }
  80
  81                /* Set all columns to low */
  82                regmap_update_bits(priv->syscon, SYSCON_OFFSET,
  83                                   SYSCON1_KBDSCAN_MASK, SYSCON1_KBDSCAN(1));
  84        }
  85
  86        if (sync)
  87                input_sync(dev->input);
  88}
  89
  90static int clps711x_keypad_probe(struct platform_device *pdev)
  91{
  92        struct clps711x_keypad_data *priv;
  93        struct device *dev = &pdev->dev;
  94        struct device_node *np = dev->of_node;
  95        struct input_polled_dev *poll_dev;
  96        u32 poll_interval;
  97        int i, err;
  98
  99        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 100        if (!priv)
 101                return -ENOMEM;
 102
 103        priv->syscon =
 104                syscon_regmap_lookup_by_compatible("cirrus,clps711x-syscon1");
 105        if (IS_ERR(priv->syscon))
 106                return PTR_ERR(priv->syscon);
 107
 108        priv->row_count = of_gpio_named_count(np, "row-gpios");
 109        if (priv->row_count < 1)
 110                return -EINVAL;
 111
 112        priv->gpio_data = devm_kzalloc(dev,
 113                                sizeof(*priv->gpio_data) * priv->row_count,
 114                                GFP_KERNEL);
 115        if (!priv->gpio_data)
 116                return -ENOMEM;
 117
 118        priv->row_shift = get_count_order(CLPS711X_KEYPAD_COL_COUNT);
 119
 120        for (i = 0; i < priv->row_count; i++) {
 121                struct clps711x_gpio_data *data = &priv->gpio_data[i];
 122
 123                data->desc = devm_gpiod_get_index(dev, "row", i, GPIOD_IN);
 124                if (IS_ERR(data->desc))
 125                        return PTR_ERR(data->desc);
 126        }
 127
 128        err = of_property_read_u32(np, "poll-interval", &poll_interval);
 129        if (err)
 130                return err;
 131
 132        poll_dev = input_allocate_polled_device();
 133        if (!poll_dev)
 134                return -ENOMEM;
 135
 136        poll_dev->private               = priv;
 137        poll_dev->poll                  = clps711x_keypad_poll;
 138        poll_dev->poll_interval         = poll_interval;
 139        poll_dev->input->name           = pdev->name;
 140        poll_dev->input->dev.parent     = dev;
 141        poll_dev->input->id.bustype     = BUS_HOST;
 142        poll_dev->input->id.vendor      = 0x0001;
 143        poll_dev->input->id.product     = 0x0001;
 144        poll_dev->input->id.version     = 0x0100;
 145
 146        err = matrix_keypad_build_keymap(NULL, NULL, priv->row_count,
 147                                         CLPS711X_KEYPAD_COL_COUNT,
 148                                         NULL, poll_dev->input);
 149        if (err)
 150                goto out_err;
 151
 152        input_set_capability(poll_dev->input, EV_MSC, MSC_SCAN);
 153        if (of_property_read_bool(np, "autorepeat"))
 154                __set_bit(EV_REP, poll_dev->input->evbit);
 155
 156        platform_set_drvdata(pdev, poll_dev);
 157
 158        /* Set all columns to low */
 159        regmap_update_bits(priv->syscon, SYSCON_OFFSET, SYSCON1_KBDSCAN_MASK,
 160                           SYSCON1_KBDSCAN(1));
 161
 162        err = input_register_polled_device(poll_dev);
 163        if (err)
 164                goto out_err;
 165
 166        return 0;
 167
 168out_err:
 169        input_free_polled_device(poll_dev);
 170        return err;
 171}
 172
 173static int clps711x_keypad_remove(struct platform_device *pdev)
 174{
 175        struct input_polled_dev *poll_dev = platform_get_drvdata(pdev);
 176
 177        input_unregister_polled_device(poll_dev);
 178        input_free_polled_device(poll_dev);
 179
 180        return 0;
 181}
 182
 183static const struct of_device_id clps711x_keypad_of_match[] = {
 184        { .compatible = "cirrus,clps711x-keypad", },
 185        { }
 186};
 187MODULE_DEVICE_TABLE(of, clps711x_keypad_of_match);
 188
 189static struct platform_driver clps711x_keypad_driver = {
 190        .driver = {
 191                .name           = "clps711x-keypad",
 192                .of_match_table = clps711x_keypad_of_match,
 193        },
 194        .probe  = clps711x_keypad_probe,
 195        .remove = clps711x_keypad_remove,
 196};
 197module_platform_driver(clps711x_keypad_driver);
 198
 199MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
 200MODULE_DESCRIPTION("Cirrus Logic CLPS711X Keypad driver");
 201MODULE_LICENSE("GPL");
 202
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.