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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LM8333 keypad driver
  4 * Copyright (C) 2012 Wolfram Sang, Pengutronix <kernel@pengutronix.de>
  5 */
  6
  7#include <linux/i2c.h>
  8#include <linux/input.h>
  9#include <linux/input/matrix_keypad.h>
 10#include <linux/input/lm8333.h>
 11#include <linux/interrupt.h>
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14
 15#define LM8333_FIFO_READ		0x20
 16#define LM8333_DEBOUNCE			0x22
 17#define LM8333_READ_INT			0xD0
 18#define LM8333_ACTIVE			0xE4
 19#define LM8333_READ_ERROR		0xF0
 20
 21#define LM8333_KEYPAD_IRQ		(1 << 0)
 22#define LM8333_ERROR_IRQ		(1 << 3)
 23
 24#define LM8333_ERROR_KEYOVR		0x04
 25#define LM8333_ERROR_FIFOOVR		0x40
 26
 27#define LM8333_FIFO_TRANSFER_SIZE	16
 28
 29#define LM8333_NUM_ROWS		8
 30#define LM8333_NUM_COLS		16
 31#define LM8333_ROW_SHIFT	4
 32
 33struct lm8333 {
 34	struct i2c_client *client;
 35	struct input_dev *input;
 36	unsigned short keycodes[LM8333_NUM_ROWS << LM8333_ROW_SHIFT];
 37};
 38
 39/* The accessors try twice because the first access may be needed for wakeup */
 40#define LM8333_READ_RETRIES 2
 41
 42int lm8333_read8(struct lm8333 *lm8333, u8 cmd)
 43{
 44	int retries = 0, ret;
 45
 46	do {
 47		ret = i2c_smbus_read_byte_data(lm8333->client, cmd);
 48	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 49
 50	return ret;
 51}
 52
 53int lm8333_write8(struct lm8333 *lm8333, u8 cmd, u8 val)
 54{
 55	int retries = 0, ret;
 56
 57	do {
 58		ret = i2c_smbus_write_byte_data(lm8333->client, cmd, val);
 59	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 60
 61	return ret;
 62}
 63
 64int lm8333_read_block(struct lm8333 *lm8333, u8 cmd, u8 len, u8 *buf)
 65{
 66	int retries = 0, ret;
 67
 68	do {
 69		ret = i2c_smbus_read_i2c_block_data(lm8333->client,
 70						    cmd, len, buf);
 71	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 72
 73	return ret;
 74}
 75
 76static void lm8333_key_handler(struct lm8333 *lm8333)
 77{
 78	struct input_dev *input = lm8333->input;
 79	u8 keys[LM8333_FIFO_TRANSFER_SIZE];
 80	u8 code, pressed;
 81	int i, ret;
 82
 83	ret = lm8333_read_block(lm8333, LM8333_FIFO_READ,
 84				LM8333_FIFO_TRANSFER_SIZE, keys);
 85	if (ret != LM8333_FIFO_TRANSFER_SIZE) {
 86		dev_err(&lm8333->client->dev,
 87			"Error %d while reading FIFO\n", ret);
 88		return;
 89	}
 90
 91	for (i = 0; i < LM8333_FIFO_TRANSFER_SIZE && keys[i]; i++) {
 92		pressed = keys[i] & 0x80;
 93		code = keys[i] & 0x7f;
 94
 95		input_event(input, EV_MSC, MSC_SCAN, code);
 96		input_report_key(input, lm8333->keycodes[code], pressed);
 97	}
 98
 99	input_sync(input);
100}
101
102static irqreturn_t lm8333_irq_thread(int irq, void *data)
103{
104	struct lm8333 *lm8333 = data;
105	u8 status = lm8333_read8(lm8333, LM8333_READ_INT);
106
107	if (!status)
108		return IRQ_NONE;
109
110	if (status & LM8333_ERROR_IRQ) {
111		u8 err = lm8333_read8(lm8333, LM8333_READ_ERROR);
112
113		if (err & (LM8333_ERROR_KEYOVR | LM8333_ERROR_FIFOOVR)) {
114			u8 dummy[LM8333_FIFO_TRANSFER_SIZE];
115
116			lm8333_read_block(lm8333, LM8333_FIFO_READ,
117					LM8333_FIFO_TRANSFER_SIZE, dummy);
118		}
119		dev_err(&lm8333->client->dev, "Got error %02x\n", err);
120	}
121
122	if (status & LM8333_KEYPAD_IRQ)
123		lm8333_key_handler(lm8333);
124
125	return IRQ_HANDLED;
126}
127
128static int lm8333_probe(struct i2c_client *client)
129{
130	const struct lm8333_platform_data *pdata =
131			dev_get_platdata(&client->dev);
132	struct lm8333 *lm8333;
133	struct input_dev *input;
134	int err, active_time;
135
136	if (!pdata)
137		return -EINVAL;
138
139	active_time = pdata->active_time ?: 500;
140	if (active_time / 3 <= pdata->debounce_time / 3) {
141		dev_err(&client->dev, "Active time not big enough!\n");
142		return -EINVAL;
143	}
144
145	lm8333 = kzalloc(sizeof(*lm8333), GFP_KERNEL);
146	input = input_allocate_device();
147	if (!lm8333 || !input) {
148		err = -ENOMEM;
149		goto free_mem;
150	}
 
151
152	lm8333->client = client;
153	lm8333->input = input;
154
155	input->name = client->name;
156	input->dev.parent = &client->dev;
157	input->id.bustype = BUS_I2C;
158
159	input_set_capability(input, EV_MSC, MSC_SCAN);
160
161	err = matrix_keypad_build_keymap(pdata->matrix_data, NULL,
162					 LM8333_NUM_ROWS, LM8333_NUM_COLS,
163					 lm8333->keycodes, input);
164	if (err)
165		goto free_mem;
166
167	if (pdata->debounce_time) {
168		err = lm8333_write8(lm8333, LM8333_DEBOUNCE,
169				    pdata->debounce_time / 3);
170		if (err)
171			dev_warn(&client->dev, "Unable to set debounce time\n");
172	}
173
174	if (pdata->active_time) {
175		err = lm8333_write8(lm8333, LM8333_ACTIVE,
176				    pdata->active_time / 3);
177		if (err)
178			dev_warn(&client->dev, "Unable to set active time\n");
179	}
180
181	err = request_threaded_irq(client->irq, NULL, lm8333_irq_thread,
182				   IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
183				   "lm8333", lm8333);
 
184	if (err)
185		goto free_mem;
186
187	err = input_register_device(input);
188	if (err)
189		goto free_irq;
190
191	i2c_set_clientdata(client, lm8333);
192	return 0;
193
194 free_irq:
195	free_irq(client->irq, lm8333);
196 free_mem:
197	input_free_device(input);
198	kfree(lm8333);
199	return err;
200}
201
202static void lm8333_remove(struct i2c_client *client)
203{
204	struct lm8333 *lm8333 = i2c_get_clientdata(client);
205
206	free_irq(client->irq, lm8333);
207	input_unregister_device(lm8333->input);
208	kfree(lm8333);
209}
210
211static const struct i2c_device_id lm8333_id[] = {
212	{ "lm8333", 0 },
213	{ }
214};
215MODULE_DEVICE_TABLE(i2c, lm8333_id);
216
217static struct i2c_driver lm8333_driver = {
218	.driver = {
219		.name		= "lm8333",
220	},
221	.probe_new	= lm8333_probe,
222	.remove		= lm8333_remove,
223	.id_table	= lm8333_id,
224};
225module_i2c_driver(lm8333_driver);
226
227MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
228MODULE_DESCRIPTION("LM8333 keyboard driver");
229MODULE_LICENSE("GPL v2");
v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LM8333 keypad driver
  4 * Copyright (C) 2012 Wolfram Sang, Pengutronix <kernel@pengutronix.de>
  5 */
  6
  7#include <linux/i2c.h>
  8#include <linux/input.h>
  9#include <linux/input/matrix_keypad.h>
 10#include <linux/input/lm8333.h>
 11#include <linux/interrupt.h>
 12#include <linux/module.h>
 13#include <linux/slab.h>
 14
 15#define LM8333_FIFO_READ		0x20
 16#define LM8333_DEBOUNCE			0x22
 17#define LM8333_READ_INT			0xD0
 18#define LM8333_ACTIVE			0xE4
 19#define LM8333_READ_ERROR		0xF0
 20
 21#define LM8333_KEYPAD_IRQ		(1 << 0)
 22#define LM8333_ERROR_IRQ		(1 << 3)
 23
 24#define LM8333_ERROR_KEYOVR		0x04
 25#define LM8333_ERROR_FIFOOVR		0x40
 26
 27#define LM8333_FIFO_TRANSFER_SIZE	16
 28
 29#define LM8333_NUM_ROWS		8
 30#define LM8333_NUM_COLS		16
 31#define LM8333_ROW_SHIFT	4
 32
 33struct lm8333 {
 34	struct i2c_client *client;
 35	struct input_dev *input;
 36	unsigned short keycodes[LM8333_NUM_ROWS << LM8333_ROW_SHIFT];
 37};
 38
 39/* The accessors try twice because the first access may be needed for wakeup */
 40#define LM8333_READ_RETRIES 2
 41
 42int lm8333_read8(struct lm8333 *lm8333, u8 cmd)
 43{
 44	int retries = 0, ret;
 45
 46	do {
 47		ret = i2c_smbus_read_byte_data(lm8333->client, cmd);
 48	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 49
 50	return ret;
 51}
 52
 53int lm8333_write8(struct lm8333 *lm8333, u8 cmd, u8 val)
 54{
 55	int retries = 0, ret;
 56
 57	do {
 58		ret = i2c_smbus_write_byte_data(lm8333->client, cmd, val);
 59	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 60
 61	return ret;
 62}
 63
 64int lm8333_read_block(struct lm8333 *lm8333, u8 cmd, u8 len, u8 *buf)
 65{
 66	int retries = 0, ret;
 67
 68	do {
 69		ret = i2c_smbus_read_i2c_block_data(lm8333->client,
 70						    cmd, len, buf);
 71	} while (ret < 0 && retries++ < LM8333_READ_RETRIES);
 72
 73	return ret;
 74}
 75
 76static void lm8333_key_handler(struct lm8333 *lm8333)
 77{
 78	struct input_dev *input = lm8333->input;
 79	u8 keys[LM8333_FIFO_TRANSFER_SIZE];
 80	u8 code, pressed;
 81	int i, ret;
 82
 83	ret = lm8333_read_block(lm8333, LM8333_FIFO_READ,
 84				LM8333_FIFO_TRANSFER_SIZE, keys);
 85	if (ret != LM8333_FIFO_TRANSFER_SIZE) {
 86		dev_err(&lm8333->client->dev,
 87			"Error %d while reading FIFO\n", ret);
 88		return;
 89	}
 90
 91	for (i = 0; i < LM8333_FIFO_TRANSFER_SIZE && keys[i]; i++) {
 92		pressed = keys[i] & 0x80;
 93		code = keys[i] & 0x7f;
 94
 95		input_event(input, EV_MSC, MSC_SCAN, code);
 96		input_report_key(input, lm8333->keycodes[code], pressed);
 97	}
 98
 99	input_sync(input);
100}
101
102static irqreturn_t lm8333_irq_thread(int irq, void *data)
103{
104	struct lm8333 *lm8333 = data;
105	u8 status = lm8333_read8(lm8333, LM8333_READ_INT);
106
107	if (!status)
108		return IRQ_NONE;
109
110	if (status & LM8333_ERROR_IRQ) {
111		u8 err = lm8333_read8(lm8333, LM8333_READ_ERROR);
112
113		if (err & (LM8333_ERROR_KEYOVR | LM8333_ERROR_FIFOOVR)) {
114			u8 dummy[LM8333_FIFO_TRANSFER_SIZE];
115
116			lm8333_read_block(lm8333, LM8333_FIFO_READ,
117					LM8333_FIFO_TRANSFER_SIZE, dummy);
118		}
119		dev_err(&lm8333->client->dev, "Got error %02x\n", err);
120	}
121
122	if (status & LM8333_KEYPAD_IRQ)
123		lm8333_key_handler(lm8333);
124
125	return IRQ_HANDLED;
126}
127
128static int lm8333_probe(struct i2c_client *client)
129{
130	const struct lm8333_platform_data *pdata =
131			dev_get_platdata(&client->dev);
132	struct lm8333 *lm8333;
133	struct input_dev *input;
134	int err, active_time;
135
136	if (!pdata)
137		return -EINVAL;
138
139	active_time = pdata->active_time ?: 500;
140	if (active_time / 3 <= pdata->debounce_time / 3) {
141		dev_err(&client->dev, "Active time not big enough!\n");
142		return -EINVAL;
143	}
144
145	lm8333 = devm_kzalloc(&client->dev, sizeof(*lm8333), GFP_KERNEL);
146	if (!lm8333)
147		return -ENOMEM;
148
149	input = devm_input_allocate_device(&client->dev);
150	if (!input)
151		return -ENOMEM;
152
153	lm8333->client = client;
154	lm8333->input = input;
155
156	input->name = client->name;
 
157	input->id.bustype = BUS_I2C;
158
159	input_set_capability(input, EV_MSC, MSC_SCAN);
160
161	err = matrix_keypad_build_keymap(pdata->matrix_data, NULL,
162					 LM8333_NUM_ROWS, LM8333_NUM_COLS,
163					 lm8333->keycodes, input);
164	if (err)
165		return err;
166
167	if (pdata->debounce_time) {
168		err = lm8333_write8(lm8333, LM8333_DEBOUNCE,
169				    pdata->debounce_time / 3);
170		if (err)
171			dev_warn(&client->dev, "Unable to set debounce time\n");
172	}
173
174	if (pdata->active_time) {
175		err = lm8333_write8(lm8333, LM8333_ACTIVE,
176				    pdata->active_time / 3);
177		if (err)
178			dev_warn(&client->dev, "Unable to set active time\n");
179	}
180
181	err = devm_request_threaded_irq(&client->dev, client->irq,
182					NULL, lm8333_irq_thread,
183					IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
184					"lm8333", lm8333);
185	if (err)
186		return err;
187
188	err = input_register_device(input);
189	if (err)
190		return err;
191
192	i2c_set_clientdata(client, lm8333);
193	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
194}
195
196static const struct i2c_device_id lm8333_id[] = {
197	{ "lm8333", 0 },
198	{ }
199};
200MODULE_DEVICE_TABLE(i2c, lm8333_id);
201
202static struct i2c_driver lm8333_driver = {
203	.driver = {
204		.name		= "lm8333",
205	},
206	.probe		= lm8333_probe,
 
207	.id_table	= lm8333_id,
208};
209module_i2c_driver(lm8333_driver);
210
211MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
212MODULE_DESCRIPTION("LM8333 keyboard driver");
213MODULE_LICENSE("GPL v2");