1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2022 MediaTek Inc. 4 * Author Fengping Yu <fengping.yu@mediatek.com> 5 */ 6 #include <linux/bitops.h> 7 #include <linux/clk.h> 8 #include <linux/input/matrix_keypad.h> 9 #include <linux/interrupt.h> 10 #include <linux/module.h> 11 #include <linux/property.h> 12 #include <linux/platform_device.h> 13 #include <linux/regmap.h> 14 15 #define MTK_KPD_NAME "mt6779-keypad" 16 #define MTK_KPD_MEM 0x0004 17 #define MTK_KPD_DEBOUNCE 0x0018 18 #define MTK_KPD_DEBOUNCE_MASK GENMASK(13, 0) 19 #define MTK_KPD_DEBOUNCE_MAX_MS 256 20 #define MTK_KPD_NUM_MEMS 5 21 #define MTK_KPD_NUM_BITS 136 /* 4*32+8 MEM5 only use 8 BITS */ 22 23 struct mt6779_keypad { 24 struct regmap *regmap; 25 struct input_dev *input_dev; 26 struct clk *clk; 27 void __iomem *base; 28 u32 n_rows; 29 u32 n_cols; 30 DECLARE_BITMAP(keymap_state, MTK_KPD_NUM_BITS); 31 }; 32 33 static const struct regmap_config mt6779_keypad_regmap_cfg = { 34 .reg_bits = 32, 35 .val_bits = 32, 36 .reg_stride = sizeof(u32), 37 .max_register = 36, 38 }; 39 40 static irqreturn_t mt6779_keypad_irq_handler(int irq, void *dev_id) 41 { 42 struct mt6779_keypad *keypad = dev_id; 43 const unsigned short *keycode = keypad->input_dev->keycode; 44 DECLARE_BITMAP(new_state, MTK_KPD_NUM_BITS); 45 DECLARE_BITMAP(change, MTK_KPD_NUM_BITS); 46 unsigned int bit_nr; 47 unsigned int row, col; 48 unsigned int scancode; 49 unsigned int row_shift = get_count_order(keypad->n_cols); 50 bool pressed; 51 52 regmap_bulk_read(keypad->regmap, MTK_KPD_MEM, 53 new_state, MTK_KPD_NUM_MEMS); 54 55 bitmap_xor(change, new_state, keypad->keymap_state, MTK_KPD_NUM_BITS); 56 57 for_each_set_bit(bit_nr, change, MTK_KPD_NUM_BITS) { 58 /* 59 * Registers are 32bits, but only bits [15:0] are used to 60 * indicate key status. 61 */ 62 if (bit_nr % 32 >= 16) 63 continue; 64 65 row = bit_nr / 32; 66 col = bit_nr % 32; 67 scancode = MATRIX_SCAN_CODE(row, col, row_shift); 68 /* 1: not pressed, 0: pressed */ 69 pressed = !test_bit(bit_nr, new_state); 70 dev_dbg(&keypad->input_dev->dev, "%s", 71 pressed ? "pressed" : "released"); 72 73 input_event(keypad->input_dev, EV_MSC, MSC_SCAN, scancode); 74 input_report_key(keypad->input_dev, keycode[scancode], pressed); 75 input_sync(keypad->input_dev); 76 77 dev_dbg(&keypad->input_dev->dev, 78 "report Linux keycode = %d\n", keycode[scancode]); 79 } 80 81 bitmap_copy(keypad->keymap_state, new_state, MTK_KPD_NUM_BITS); 82 83 return IRQ_HANDLED; 84 } 85 86 static void mt6779_keypad_clk_disable(void *data) 87 { 88 clk_disable_unprepare(data); 89 } 90 91 static int mt6779_keypad_pdrv_probe(struct platform_device *pdev) 92 { 93 struct mt6779_keypad *keypad; 94 unsigned int irq; 95 u32 debounce; 96 bool wakeup; 97 int error; 98 99 keypad = devm_kzalloc(&pdev->dev, sizeof(*keypad), GFP_KERNEL); 100 if (!keypad) 101 return -ENOMEM; 102 103 keypad->base = devm_platform_ioremap_resource(pdev, 0); 104 if (IS_ERR(keypad->base)) 105 return PTR_ERR(keypad->base); 106 107 keypad->regmap = devm_regmap_init_mmio(&pdev->dev, keypad->base, 108 &mt6779_keypad_regmap_cfg); 109 if (IS_ERR(keypad->regmap)) { 110 dev_err(&pdev->dev, 111 "regmap init failed:%pe\n", keypad->regmap); 112 return PTR_ERR(keypad->regmap); 113 } 114 115 bitmap_fill(keypad->keymap_state, MTK_KPD_NUM_BITS); 116 117 keypad->input_dev = devm_input_allocate_device(&pdev->dev); 118 if (!keypad->input_dev) { 119 dev_err(&pdev->dev, "Failed to allocate input dev\n"); 120 return -ENOMEM; 121 } 122 123 keypad->input_dev->name = MTK_KPD_NAME; 124 keypad->input_dev->id.bustype = BUS_HOST; 125 126 error = matrix_keypad_parse_properties(&pdev->dev, &keypad->n_rows, 127 &keypad->n_cols); 128 if (error) { 129 dev_err(&pdev->dev, "Failed to parse keypad params\n"); 130 return error; 131 } 132 133 if (device_property_read_u32(&pdev->dev, "debounce-delay-ms", 134 &debounce)) 135 debounce = 16; 136 137 if (debounce > MTK_KPD_DEBOUNCE_MAX_MS) { 138 dev_err(&pdev->dev, 139 "Debounce time exceeds the maximum allowed time %dms\n", 140 MTK_KPD_DEBOUNCE_MAX_MS); 141 return -EINVAL; 142 } 143 144 wakeup = device_property_read_bool(&pdev->dev, "wakeup-source"); 145 146 dev_dbg(&pdev->dev, "n_row=%d n_col=%d debounce=%d\n", 147 keypad->n_rows, keypad->n_cols, debounce); 148 149 error = matrix_keypad_build_keymap(NULL, NULL, 150 keypad->n_rows, keypad->n_cols, 151 NULL, keypad->input_dev); 152 if (error) { 153 dev_err(&pdev->dev, "Failed to build keymap\n"); 154 return error; 155 } 156 157 input_set_capability(keypad->input_dev, EV_MSC, MSC_SCAN); 158 159 regmap_write(keypad->regmap, MTK_KPD_DEBOUNCE, 160 (debounce * (1 << 5)) & MTK_KPD_DEBOUNCE_MASK); 161 162 keypad->clk = devm_clk_get(&pdev->dev, "kpd"); 163 if (IS_ERR(keypad->clk)) 164 return PTR_ERR(keypad->clk); 165 166 error = clk_prepare_enable(keypad->clk); 167 if (error) { 168 dev_err(&pdev->dev, "cannot prepare/enable keypad clock\n"); 169 return error; 170 } 171 172 error = devm_add_action_or_reset(&pdev->dev, mt6779_keypad_clk_disable, 173 keypad->clk); 174 if (error) 175 return error; 176 177 irq = platform_get_irq(pdev, 0); 178 if (irq < 0) 179 return irq; 180 181 error = devm_request_threaded_irq(&pdev->dev, irq, 182 NULL, mt6779_keypad_irq_handler, 183 IRQF_ONESHOT, MTK_KPD_NAME, keypad); 184 if (error) { 185 dev_err(&pdev->dev, "Failed to request IRQ#%d: %d\n", 186 irq, error); 187 return error; 188 } 189 190 error = input_register_device(keypad->input_dev); 191 if (error) { 192 dev_err(&pdev->dev, "Failed to register device\n"); 193 return error; 194 } 195 196 error = device_init_wakeup(&pdev->dev, wakeup); 197 if (error) 198 dev_warn(&pdev->dev, "device_init_wakeup() failed: %d\n", 199 error); 200 201 return 0; 202 } 203 204 static const struct of_device_id mt6779_keypad_of_match[] = { 205 { .compatible = "mediatek,mt6779-keypad" }, 206 { .compatible = "mediatek,mt6873-keypad" }, 207 { /* sentinel */ } 208 }; 209 210 static struct platform_driver mt6779_keypad_pdrv = { 211 .probe = mt6779_keypad_pdrv_probe, 212 .driver = { 213 .name = MTK_KPD_NAME, 214 .of_match_table = mt6779_keypad_of_match, 215 }, 216 }; 217 module_platform_driver(mt6779_keypad_pdrv); 218 219 MODULE_AUTHOR("Mediatek Corporation"); 220 MODULE_DESCRIPTION("MTK Keypad (KPD) Driver"); 221 MODULE_LICENSE("GPL"); 222