// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2007-2008 Extreme Engineering Solutions, Inc. * * Author: Nate Case <[email protected]> * * LED driver for various PCA955x I2C LED drivers * * Supported devices: * * Device Description 7-bit slave address * ------ ----------- ------------------- * PCA9550 2-bit driver 0x60 .. 0x61 * PCA9551 8-bit driver 0x60 .. 0x67 * PCA9552 16-bit driver 0x60 .. 0x67 * PCA9553/01 4-bit driver 0x62 * PCA9553/02 4-bit driver 0x63 * * Philips PCA955x LED driver chips follow a register map as shown below: * * Control Register Description * ---------------- ----------- * 0x0 Input register 0 * .. * NUM_INPUT_REGS - 1 Last Input register X * * NUM_INPUT_REGS Frequency prescaler 0 * NUM_INPUT_REGS + 1 PWM register 0 * NUM_INPUT_REGS + 2 Frequency prescaler 1 * NUM_INPUT_REGS + 3 PWM register 1 * * NUM_INPUT_REGS + 4 LED selector 0 * NUM_INPUT_REGS + 4 * + NUM_LED_REGS - 1 Last LED selector * * where NUM_INPUT_REGS and NUM_LED_REGS vary depending on how many * bits the chip supports. */ #include <linux/bitops.h> #include <linux/ctype.h> #include <linux/delay.h> #include <linux/err.h> #include <linux/gpio/driver.h> #include <linux/i2c.h> #include <linux/leds.h> #include <linux/module.h> #include <linux/of.h> #include <linux/property.h> #include <linux/slab.h> #include <linux/string.h> #include <dt-bindings/leds/leds-pca955x.h> /* LED select registers determine the source that drives LED outputs */ #define PCA955X_LS_LED_ON … #define PCA955X_LS_LED_OFF … #define PCA955X_LS_BLINK0 … #define PCA955X_LS_BLINK1 … #define PCA955X_GPIO_INPUT … #define PCA955X_GPIO_HIGH … #define PCA955X_GPIO_LOW … enum pca955x_type { … }; struct pca955x_chipdef { … }; static const struct pca955x_chipdef pca955x_chipdefs[] = …; struct pca955x { … }; struct pca955x_led { … }; struct pca955x_platform_data { … }; /* 8 bits per input register */ static inline int pca95xx_num_input_regs(int bits) { … } /* * Return an LED selector register value based on an existing one, with * the appropriate 2-bit state value set for the given LED number (0-3). */ static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state) { … } /* * Write to frequency prescaler register, used to program the * period of the PWM output. period = (PSCx + 1) / 38 */ static int pca955x_write_psc(struct i2c_client *client, int n, u8 val) { … } /* * Write to PWM register, which determines the duty cycle of the * output. LED is OFF when the count is less than the value of this * register, and ON when it is greater. If PWMx == 0, LED is always OFF. * * Duty cycle is (256 - PWMx) / 256 */ static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val) { … } /* * Write to LED selector register, which determines the source that * drives the LED output. */ static int pca955x_write_ls(struct i2c_client *client, int n, u8 val) { … } /* * Read the LED selector register, which determines the source that * drives the LED output. */ static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val) { … } static int pca955x_read_pwm(struct i2c_client *client, int n, u8 *val) { … } static enum led_brightness pca955x_led_get(struct led_classdev *led_cdev) { … } static int pca955x_led_set(struct led_classdev *led_cdev, enum led_brightness value) { … } #ifdef CONFIG_LEDS_PCA955X_GPIO /* * Read the INPUT register, which contains the state of LEDs. */ static int pca955x_read_input(struct i2c_client *client, int n, u8 *val) { … } static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset) { … } static void pca955x_gpio_free_pin(struct gpio_chip *gc, unsigned int offset) { … } static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset, int val) { … } static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset, int val) { … } static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset) { … } static int pca955x_gpio_direction_input(struct gpio_chip *gc, unsigned int offset) { … } static int pca955x_gpio_direction_output(struct gpio_chip *gc, unsigned int offset, int val) { … } #endif /* CONFIG_LEDS_PCA955X_GPIO */ static struct pca955x_platform_data * pca955x_get_pdata(struct i2c_client *client, const struct pca955x_chipdef *chip) { … } static int pca955x_probe(struct i2c_client *client) { … } static const struct i2c_device_id pca955x_id[] = …; MODULE_DEVICE_TABLE(i2c, pca955x_id); static const struct of_device_id of_pca955x_match[] = …; MODULE_DEVICE_TABLE(of, of_pca955x_match); static struct i2c_driver pca955x_driver = …; module_i2c_driver(…) …; MODULE_AUTHOR(…) …; MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
Codebase Browser
linux