| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | /* | 
|  | 2 | * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/ | 
|  | 3 | *	Andrew F. Davis <afd@ti.com> | 
|  | 4 | * | 
|  | 5 | * This program is free software; you can redistribute it and/or | 
|  | 6 | * modify it under the terms of the GNU General Public License version 2 as | 
|  | 7 | * published by the Free Software Foundation. | 
|  | 8 | * | 
|  | 9 | * This program is distributed "as is" WITHOUT ANY WARRANTY of any | 
|  | 10 | * kind, whether expressed or implied; without even the implied warranty | 
|  | 11 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | 12 | * GNU General Public License version 2 for more details. | 
|  | 13 | */ | 
|  | 14 |  | 
|  | 15 | #include <linux/gpio/driver.h> | 
|  | 16 | #include <linux/i2c.h> | 
|  | 17 | #include <linux/module.h> | 
|  | 18 | #include <linux/mutex.h> | 
|  | 19 |  | 
|  | 20 | #define TPIC2810_WS_COMMAND 0x44 | 
|  | 21 |  | 
|  | 22 | /** | 
|  | 23 | * struct tpic2810 - GPIO driver data | 
|  | 24 | * @chip: GPIO controller chip | 
|  | 25 | * @client: I2C device pointer | 
|  | 26 | * @buffer: Buffer for device register | 
|  | 27 | * @lock: Protects write sequences | 
|  | 28 | */ | 
|  | 29 | struct tpic2810 { | 
|  | 30 | struct gpio_chip chip; | 
|  | 31 | struct i2c_client *client; | 
|  | 32 | u8 buffer; | 
|  | 33 | struct mutex lock; | 
|  | 34 | }; | 
|  | 35 |  | 
|  | 36 | static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value); | 
|  | 37 |  | 
|  | 38 | static int tpic2810_get_direction(struct gpio_chip *chip, | 
|  | 39 | unsigned offset) | 
|  | 40 | { | 
|  | 41 | /* This device always output */ | 
|  | 42 | return 0; | 
|  | 43 | } | 
|  | 44 |  | 
|  | 45 | static int tpic2810_direction_input(struct gpio_chip *chip, | 
|  | 46 | unsigned offset) | 
|  | 47 | { | 
|  | 48 | /* This device is output only */ | 
|  | 49 | return -EINVAL; | 
|  | 50 | } | 
|  | 51 |  | 
|  | 52 | static int tpic2810_direction_output(struct gpio_chip *chip, | 
|  | 53 | unsigned offset, int value) | 
|  | 54 | { | 
|  | 55 | /* This device always output */ | 
|  | 56 | tpic2810_set(chip, offset, value); | 
|  | 57 | return 0; | 
|  | 58 | } | 
|  | 59 |  | 
|  | 60 | static void tpic2810_set_mask_bits(struct gpio_chip *chip, u8 mask, u8 bits) | 
|  | 61 | { | 
|  | 62 | struct tpic2810 *gpio = gpiochip_get_data(chip); | 
|  | 63 | u8 buffer; | 
|  | 64 | int err; | 
|  | 65 |  | 
|  | 66 | mutex_lock(&gpio->lock); | 
|  | 67 |  | 
|  | 68 | buffer = gpio->buffer & ~mask; | 
|  | 69 | buffer |= (mask & bits); | 
|  | 70 |  | 
|  | 71 | err = i2c_smbus_write_byte_data(gpio->client, TPIC2810_WS_COMMAND, | 
|  | 72 | buffer); | 
|  | 73 | if (!err) | 
|  | 74 | gpio->buffer = buffer; | 
|  | 75 |  | 
|  | 76 | mutex_unlock(&gpio->lock); | 
|  | 77 | } | 
|  | 78 |  | 
|  | 79 | static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value) | 
|  | 80 | { | 
|  | 81 | tpic2810_set_mask_bits(chip, BIT(offset), value ? BIT(offset) : 0); | 
|  | 82 | } | 
|  | 83 |  | 
|  | 84 | static void tpic2810_set_multiple(struct gpio_chip *chip, unsigned long *mask, | 
|  | 85 | unsigned long *bits) | 
|  | 86 | { | 
|  | 87 | tpic2810_set_mask_bits(chip, *mask, *bits); | 
|  | 88 | } | 
|  | 89 |  | 
|  | 90 | static const struct gpio_chip template_chip = { | 
|  | 91 | .label			= "tpic2810", | 
|  | 92 | .owner			= THIS_MODULE, | 
|  | 93 | .get_direction		= tpic2810_get_direction, | 
|  | 94 | .direction_input	= tpic2810_direction_input, | 
|  | 95 | .direction_output	= tpic2810_direction_output, | 
|  | 96 | .set			= tpic2810_set, | 
|  | 97 | .set_multiple		= tpic2810_set_multiple, | 
|  | 98 | .base			= -1, | 
|  | 99 | .ngpio			= 8, | 
|  | 100 | .can_sleep		= true, | 
|  | 101 | }; | 
|  | 102 |  | 
|  | 103 | static const struct of_device_id tpic2810_of_match_table[] = { | 
|  | 104 | { .compatible = "ti,tpic2810" }, | 
|  | 105 | { /* sentinel */ } | 
|  | 106 | }; | 
|  | 107 | MODULE_DEVICE_TABLE(of, tpic2810_of_match_table); | 
|  | 108 |  | 
|  | 109 | static int tpic2810_probe(struct i2c_client *client, | 
|  | 110 | const struct i2c_device_id *id) | 
|  | 111 | { | 
|  | 112 | struct tpic2810 *gpio; | 
|  | 113 | int ret; | 
|  | 114 |  | 
|  | 115 | gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL); | 
|  | 116 | if (!gpio) | 
|  | 117 | return -ENOMEM; | 
|  | 118 |  | 
|  | 119 | i2c_set_clientdata(client, gpio); | 
|  | 120 |  | 
|  | 121 | gpio->chip = template_chip; | 
|  | 122 | gpio->chip.parent = &client->dev; | 
|  | 123 |  | 
|  | 124 | gpio->client = client; | 
|  | 125 |  | 
|  | 126 | mutex_init(&gpio->lock); | 
|  | 127 |  | 
|  | 128 | ret = gpiochip_add_data(&gpio->chip, gpio); | 
|  | 129 | if (ret < 0) { | 
|  | 130 | dev_err(&client->dev, "Unable to register gpiochip\n"); | 
|  | 131 | return ret; | 
|  | 132 | } | 
|  | 133 |  | 
|  | 134 | return 0; | 
|  | 135 | } | 
|  | 136 |  | 
|  | 137 | static int tpic2810_remove(struct i2c_client *client) | 
|  | 138 | { | 
|  | 139 | struct tpic2810 *gpio = i2c_get_clientdata(client); | 
|  | 140 |  | 
|  | 141 | gpiochip_remove(&gpio->chip); | 
|  | 142 |  | 
|  | 143 | return 0; | 
|  | 144 | } | 
|  | 145 |  | 
|  | 146 | static const struct i2c_device_id tpic2810_id_table[] = { | 
|  | 147 | { "tpic2810", }, | 
|  | 148 | { /* sentinel */ } | 
|  | 149 | }; | 
|  | 150 | MODULE_DEVICE_TABLE(i2c, tpic2810_id_table); | 
|  | 151 |  | 
|  | 152 | static struct i2c_driver tpic2810_driver = { | 
|  | 153 | .driver = { | 
|  | 154 | .name = "tpic2810", | 
|  | 155 | .of_match_table = tpic2810_of_match_table, | 
|  | 156 | }, | 
|  | 157 | .probe = tpic2810_probe, | 
|  | 158 | .remove = tpic2810_remove, | 
|  | 159 | .id_table = tpic2810_id_table, | 
|  | 160 | }; | 
|  | 161 | module_i2c_driver(tpic2810_driver); | 
|  | 162 |  | 
|  | 163 | MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>"); | 
|  | 164 | MODULE_DESCRIPTION("TPIC2810 8-Bit LED Driver GPIO Driver"); | 
|  | 165 | MODULE_LICENSE("GPL v2"); |