Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   3)  * Driver for a keypad w/16 buttons connected to a PCF8574 I2C I/O expander
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   4)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   5)  * Copyright 2005-2008 Analog Devices Inc.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   6)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300   9) #include <linux/input.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  10) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  11) #include <linux/i2c.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  12) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  13) #include <linux/workqueue.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  15) #define DRV_NAME "pcf8574_keypad"
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  17) static const unsigned char pcf8574_kp_btncode[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  18) 	[0] = KEY_RESERVED,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  19) 	[1] = KEY_ENTER,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  20) 	[2] = KEY_BACKSLASH,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  21) 	[3] = KEY_0,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  22) 	[4] = KEY_RIGHTBRACE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  23) 	[5] = KEY_C,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  24) 	[6] = KEY_9,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  25) 	[7] = KEY_8,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  26) 	[8] = KEY_7,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  27) 	[9] = KEY_B,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  28) 	[10] = KEY_6,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  29) 	[11] = KEY_5,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  30) 	[12] = KEY_4,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  31) 	[13] = KEY_A,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  32) 	[14] = KEY_3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  33) 	[15] = KEY_2,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  34) 	[16] = KEY_1
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  35) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  36) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  37) struct kp_data {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  38) 	unsigned short btncode[ARRAY_SIZE(pcf8574_kp_btncode)];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  39) 	struct input_dev *idev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  40) 	struct i2c_client *client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  41) 	char name[64];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  42) 	char phys[32];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  43) 	unsigned char laststate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  44) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  46) static short read_state(struct kp_data *lp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  47) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  48) 	unsigned char x, y, a, b;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  49) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  50) 	i2c_smbus_write_byte(lp->client, 240);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  51) 	x = 0xF & (~(i2c_smbus_read_byte(lp->client) >> 4));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  53) 	i2c_smbus_write_byte(lp->client, 15);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  54) 	y = 0xF & (~i2c_smbus_read_byte(lp->client));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  56) 	for (a = 0; x > 0; a++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  57) 		x = x >> 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  58) 	for (b = 0; y > 0; b++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  59) 		y = y >> 1;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  61) 	return ((a - 1) * 4) + b;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  63) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  64) static irqreturn_t pcf8574_kp_irq_handler(int irq, void *dev_id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  66) 	struct kp_data *lp = dev_id;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  67) 	unsigned char nextstate = read_state(lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  69) 	if (lp->laststate != nextstate) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  70) 		int key_down = nextstate < ARRAY_SIZE(lp->btncode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  71) 		unsigned short keycode = key_down ?
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  72) 			lp->btncode[nextstate] : lp->btncode[lp->laststate];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  73) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  74) 		input_report_key(lp->idev, keycode, key_down);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  75) 		input_sync(lp->idev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  77) 		lp->laststate = nextstate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  78) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  80) 	return IRQ_HANDLED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  81) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  82) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  83) static int pcf8574_kp_probe(struct i2c_client *client, const struct i2c_device_id *id)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  84) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  85) 	int i, ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  86) 	struct input_dev *idev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  87) 	struct kp_data *lp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  88) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  89) 	if (i2c_smbus_write_byte(client, 240) < 0) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  90) 		dev_err(&client->dev, "probe: write fail\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  91) 		return -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  92) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  94) 	lp = kzalloc(sizeof(*lp), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  95) 	if (!lp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  96) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  97) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  98) 	idev = input_allocate_device();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  99) 	if (!idev) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) 		dev_err(&client->dev, "Can't allocate input device\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) 		ret = -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) 		goto fail_allocate;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) 	lp->idev = idev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) 	lp->client = client;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) 	idev->evbit[0] = BIT_MASK(EV_KEY);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) 	idev->keycode = lp->btncode;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) 	idev->keycodesize = sizeof(lp->btncode[0]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) 	idev->keycodemax = ARRAY_SIZE(lp->btncode);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) 	for (i = 0; i < ARRAY_SIZE(pcf8574_kp_btncode); i++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) 		if (lp->btncode[i] <= KEY_MAX) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) 			lp->btncode[i] = pcf8574_kp_btncode[i];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) 			__set_bit(lp->btncode[i], idev->keybit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) 	__clear_bit(KEY_RESERVED, idev->keybit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) 	sprintf(lp->name, DRV_NAME);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) 	sprintf(lp->phys, "kp_data/input0");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) 	idev->name = lp->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) 	idev->phys = lp->phys;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) 	idev->id.bustype = BUS_I2C;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) 	idev->id.vendor = 0x0001;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) 	idev->id.product = 0x0001;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) 	idev->id.version = 0x0100;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) 	lp->laststate = read_state(lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) 	ret = request_threaded_irq(client->irq, NULL, pcf8574_kp_irq_handler,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) 				   IRQF_TRIGGER_LOW | IRQF_ONESHOT,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) 				   DRV_NAME, lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) 	if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) 		dev_err(&client->dev, "IRQ %d is not free\n", client->irq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) 		goto fail_free_device;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) 	ret = input_register_device(idev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) 	if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) 		dev_err(&client->dev, "input_register_device() failed\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) 		goto fail_free_irq;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) 	i2c_set_clientdata(client, lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)  fail_free_irq:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) 	free_irq(client->irq, lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152)  fail_free_device:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) 	input_free_device(idev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)  fail_allocate:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) 	kfree(lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) static int pcf8574_kp_remove(struct i2c_client *client)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) 	struct kp_data *lp = i2c_get_clientdata(client);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) 	free_irq(client->irq, lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) 	input_unregister_device(lp->idev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) 	kfree(lp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) #ifdef CONFIG_PM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) static int pcf8574_kp_resume(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) 	struct i2c_client *client = to_i2c_client(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) 	enable_irq(client->irq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) static int pcf8574_kp_suspend(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) 	struct i2c_client *client = to_i2c_client(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) 	disable_irq(client->irq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) static const struct dev_pm_ops pcf8574_kp_pm_ops = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) 	.suspend	= pcf8574_kp_suspend,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) 	.resume		= pcf8574_kp_resume,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) # define pcf8574_kp_resume  NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) # define pcf8574_kp_suspend NULL
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) static const struct i2c_device_id pcf8574_kp_id[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) 	{ DRV_NAME, 0 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) 	{ }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) MODULE_DEVICE_TABLE(i2c, pcf8574_kp_id);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) static struct i2c_driver pcf8574_kp_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) 	.driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) 		.name  = DRV_NAME,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) #ifdef CONFIG_PM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) 		.pm = &pcf8574_kp_pm_ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) 	.probe    = pcf8574_kp_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) 	.remove   = pcf8574_kp_remove,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) 	.id_table = pcf8574_kp_id,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) module_i2c_driver(pcf8574_kp_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221) MODULE_AUTHOR("Michael Hennerich");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) MODULE_DESCRIPTION("Keypad input driver for 16 keys connected to PCF8574");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) MODULE_LICENSE("GPL");