From e14fa82439d33cef67eaafc1a48960bbfa610c8e Mon Sep 17 00:00:00 2001 From: Riku Voipio Date: Sat, 31 May 2008 14:43:41 +0100 Subject: leds: Add pca9532 led driver NXP pca9532 is a LED dimmer/controller attached to i2c bus. It allows attaching upto 16 leds which can either be on, off or dimmed and/or blinked with the two PWM modulators available. This driver is a "new-style" i2c driver that adheres to the driver model and implements the led framework api. Since the leds connected to the driver are platform specific, it is only useful when platform data is passed to the driver to define what leds are connected to which pins. Signed-off-by: Riku Voipio Signed-off-by: Andrew Morton Signed-off-by: Richard Purdie --- include/linux/leds-pca9532.h | 45 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) create mode 100644 include/linux/leds-pca9532.h (limited to 'include/linux') diff --git a/include/linux/leds-pca9532.h b/include/linux/leds-pca9532.h new file mode 100644 index 000000000000..81b4207deb95 --- /dev/null +++ b/include/linux/leds-pca9532.h @@ -0,0 +1,45 @@ +/* + * pca9532.h - platform data structure for pca9532 led controller + * + * Copyright (C) 2008 Riku Voipio + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * Datasheet: http://www.nxp.com/acrobat/datasheets/PCA9532_3.pdf + * + */ + +#ifndef __LINUX_PCA9532_H +#define __LINUX_PCA9532_H + +#include + +enum pca9532_state { + PCA9532_OFF = 0x0, + PCA9532_ON = 0x1, + PCA9532_PWM0 = 0x2, + PCA9532_PWM1 = 0x3 +}; + +enum pca9532_type { PCA9532_TYPE_NONE, PCA9532_TYPE_LED, + PCA9532_TYPE_N2100_BEEP }; + +struct pca9532_led { + u8 id; + struct i2c_client *client; + char *name; + struct led_classdev ldev; + enum pca9532_type type; + enum pca9532_state state; +}; + +struct pca9532_platform_data { + struct pca9532_led leds[16]; + u8 pwm[2]; + u8 psc[2]; +}; + +#endif /* __LINUX_PCA9532_H */ + -- cgit v1.2.3-58-ga151 From 781a54e7664cc0089287a90d27086e9656ac68a1 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Sat, 31 May 2008 15:23:19 +0100 Subject: leds: mark led_classdev.default_trigger as const LED classdev core doesn't modify memory pointed by the default_trigger, so mark it as const and we'll able to pass const char *s without getting compiler warnings. Signed-off-by: Anton Vorontsov Signed-off-by: Richard Purdie --- include/linux/leds.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/leds.h b/include/linux/leds.h index 519df72e939d..e7a5e89932fe 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -48,7 +48,7 @@ struct led_classdev { struct device *dev; struct list_head node; /* LED Device list */ - char *default_trigger; /* Trigger to use */ + const char *default_trigger; /* Trigger to use */ #ifdef CONFIG_LEDS_TRIGGERS /* Protects the trigger data below */ -- cgit v1.2.3-58-ga151 From f46e9203d9a100bae216cc06e17f2e77351aa8d8 Mon Sep 17 00:00:00 2001 From: Nate Case Date: Wed, 16 Jul 2008 22:49:55 +0100 Subject: leds: Add support for Philips PCA955x I2C LED drivers This driver supports the PCA9550, PCA9551, PCA9552, and PCA9553 LED driver chips. Signed-off-by: Nate Case Signed-off-by: Andrew Morton Signed-off-by: Richard Purdie --- drivers/leds/Kconfig | 8 + drivers/leds/Makefile | 1 + drivers/leds/leds-pca955x.c | 384 ++++++++++++++++++++++++++++++++++++++++++++ include/linux/leds.h | 14 ++ 4 files changed, 407 insertions(+) create mode 100644 drivers/leds/leds-pca955x.c (limited to 'include/linux') diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 1c35dfaef721..9556262dda5a 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -155,6 +155,14 @@ config LEDS_CLEVO_MAIL To compile this driver as a module, choose M here: the module will be called leds-clevo-mail. +config LEDS_PCA955X + tristate "LED Support for PCA955x I2C chips" + depends on LEDS_CLASS && I2C + help + This option enables support for LEDs connected to PCA955x + LED driver chips accessed via the I2C bus. Supported + devices include PCA9550, PCA9551, PCA9552, and PCA9553. + comment "LED Triggers" config LEDS_TRIGGERS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 7156f9970fa9..ff7982b44565 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_LEDS_CM_X270) += leds-cm-x270.o obj-$(CONFIG_LEDS_CLEVO_MAIL) += leds-clevo-mail.o obj-$(CONFIG_LEDS_HP6XX) += leds-hp6xx.o obj-$(CONFIG_LEDS_FSG) += leds-fsg.o +obj-$(CONFIG_LEDS_PCA955X) += leds-pca955x.o # LED Triggers obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o diff --git a/drivers/leds/leds-pca955x.c b/drivers/leds/leds-pca955x.c new file mode 100644 index 000000000000..146c06972863 --- /dev/null +++ b/drivers/leds/leds-pca955x.c @@ -0,0 +1,384 @@ +/* + * Copyright 2007-2008 Extreme Engineering Solutions, Inc. + * + * Author: Nate Case + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * 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 +#include +#include +#include +#include +#include +#include +#include + +/* LED select registers determine the source that drives LED outputs */ +#define PCA955X_LS_LED_ON 0x0 /* Output LOW */ +#define PCA955X_LS_LED_OFF 0x1 /* Output HI-Z */ +#define PCA955X_LS_BLINK0 0x2 /* Blink at PWM0 rate */ +#define PCA955X_LS_BLINK1 0x3 /* Blink at PWM1 rate */ + +enum pca955x_type { + pca9550, + pca9551, + pca9552, + pca9553, +}; + +struct pca955x_chipdef { + int bits; + u8 slv_addr; /* 7-bit slave address mask */ + int slv_addr_shift; /* Number of bits to ignore */ +}; + +static struct pca955x_chipdef pca955x_chipdefs[] = { + [pca9550] = { + .bits = 2, + .slv_addr = /* 110000x */ 0x60, + .slv_addr_shift = 1, + }, + [pca9551] = { + .bits = 8, + .slv_addr = /* 1100xxx */ 0x60, + .slv_addr_shift = 3, + }, + [pca9552] = { + .bits = 16, + .slv_addr = /* 1100xxx */ 0x60, + .slv_addr_shift = 3, + }, + [pca9553] = { + .bits = 4, + .slv_addr = /* 110001x */ 0x62, + .slv_addr_shift = 1, + }, +}; + +static const struct i2c_device_id pca955x_id[] = { + { "pca9550", pca9550 }, + { "pca9551", pca9551 }, + { "pca9552", pca9552 }, + { "pca9553", pca9553 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, pca955x_id); + +struct pca955x_led { + struct pca955x_chipdef *chipdef; + struct i2c_client *client; + struct work_struct work; + spinlock_t lock; + enum led_brightness brightness; + struct led_classdev led_cdev; + int led_num; /* 0 .. 15 potentially */ + char name[32]; +}; + +/* 8 bits per input register */ +static inline int pca95xx_num_input_regs(int bits) +{ + return (bits + 7) / 8; +} + +/* 4 bits per LED selector register */ +static inline int pca95xx_num_led_regs(int bits) +{ + return (bits + 3) / 4; +} + +/* + * 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) +{ + return (oldval & (~(0x3 << (led_num << 1)))) | + ((state & 0x3) << (led_num << 1)); +} + +/* + * Write to frequency prescaler register, used to program the + * period of the PWM output. period = (PSCx + 1) / 38 + */ +static void pca955x_write_psc(struct i2c_client *client, int n, u8 val) +{ + struct pca955x_led *pca955x = i2c_get_clientdata(client); + + i2c_smbus_write_byte_data(client, + pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n, + 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 void pca955x_write_pwm(struct i2c_client *client, int n, u8 val) +{ + struct pca955x_led *pca955x = i2c_get_clientdata(client); + + i2c_smbus_write_byte_data(client, + pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n, + val); +} + +/* + * Write to LED selector register, which determines the source that + * drives the LED output. + */ +static void pca955x_write_ls(struct i2c_client *client, int n, u8 val) +{ + struct pca955x_led *pca955x = i2c_get_clientdata(client); + + i2c_smbus_write_byte_data(client, + pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n, + val); +} + +/* + * Read the LED selector register, which determines the source that + * drives the LED output. + */ +static u8 pca955x_read_ls(struct i2c_client *client, int n) +{ + struct pca955x_led *pca955x = i2c_get_clientdata(client); + + return (u8) i2c_smbus_read_byte_data(client, + pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n); +} + +static void pca955x_led_work(struct work_struct *work) +{ + struct pca955x_led *pca955x; + u8 ls; + int chip_ls; /* which LSx to use (0-3 potentially) */ + int ls_led; /* which set of bits within LSx to use (0-3) */ + + pca955x = container_of(work, struct pca955x_led, work); + chip_ls = pca955x->led_num / 4; + ls_led = pca955x->led_num % 4; + + ls = pca955x_read_ls(pca955x->client, chip_ls); + + switch (pca955x->brightness) { + case LED_FULL: + ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_ON); + break; + case LED_OFF: + ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_LED_OFF); + break; + case LED_HALF: + ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK0); + break; + default: + /* + * Use PWM1 for all other values. This has the unwanted + * side effect of making all LEDs on the chip share the + * same brightness level if set to a value other than + * OFF, HALF, or FULL. But, this is probably better than + * just turning off for all other values. + */ + pca955x_write_pwm(pca955x->client, 1, 255-pca955x->brightness); + ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1); + break; + } + + pca955x_write_ls(pca955x->client, chip_ls, ls); +} + +void pca955x_led_set(struct led_classdev *led_cdev, enum led_brightness value) +{ + struct pca955x_led *pca955x; + + pca955x = container_of(led_cdev, struct pca955x_led, led_cdev); + + spin_lock(&pca955x->lock); + pca955x->brightness = value; + + /* + * Must use workqueue for the actual I/O since I2C operations + * can sleep. + */ + schedule_work(&pca955x->work); + + spin_unlock(&pca955x->lock); +} + +static int __devinit pca955x_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct pca955x_led *pca955x; + int i; + int err = -ENODEV; + struct pca955x_chipdef *chip; + struct i2c_adapter *adapter; + struct led_platform_data *pdata; + + chip = &pca955x_chipdefs[id->driver_data]; + adapter = to_i2c_adapter(client->dev.parent); + pdata = client->dev.platform_data; + + /* Make sure the slave address / chip type combo given is possible */ + if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) != + chip->slv_addr) { + dev_err(&client->dev, "invalid slave address %02x\n", + client->addr); + return -ENODEV; + } + + printk(KERN_INFO "leds-pca955x: Using %s %d-bit LED driver at " + "slave address 0x%02x\n", + id->name, chip->bits, client->addr); + + if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) + return -EIO; + + if (pdata) { + if (pdata->num_leds != chip->bits) { + dev_err(&client->dev, "board info claims %d LEDs" + " on a %d-bit chip\n", + pdata->num_leds, chip->bits); + return -ENODEV; + } + } + + for (i = 0; i < chip->bits; i++) { + pca955x = kzalloc(sizeof(struct pca955x_led), GFP_KERNEL); + if (!pca955x) { + err = -ENOMEM; + goto exit; + } + + pca955x->chipdef = chip; + pca955x->client = client; + pca955x->led_num = i; + /* Platform data can specify LED names and default triggers */ + if (pdata) { + if (pdata->leds[i].name) + snprintf(pca955x->name, 32, "pca955x:%s", + pdata->leds[i].name); + if (pdata->leds[i].default_trigger) + pca955x->led_cdev.default_trigger = + pdata->leds[i].default_trigger; + } else { + snprintf(pca955x->name, 32, "pca955x:%d", i); + } + spin_lock_init(&pca955x->lock); + + pca955x->led_cdev.name = pca955x->name; + pca955x->led_cdev.brightness_set = + pca955x_led_set; + + /* + * Client data is a pointer to the _first_ pca955x_led + * struct + */ + if (i == 0) + i2c_set_clientdata(client, pca955x); + + INIT_WORK(&(pca955x->work), pca955x_led_work); + + led_classdev_register(&client->dev, &(pca955x->led_cdev)); + } + + /* Turn off LEDs */ + for (i = 0; i < pca95xx_num_led_regs(chip->bits); i++) + pca955x_write_ls(client, i, 0x55); + + /* PWM0 is used for half brightness or 50% duty cycle */ + pca955x_write_pwm(client, 0, 255-LED_HALF); + + /* PWM1 is used for variable brightness, default to OFF */ + pca955x_write_pwm(client, 1, 0); + + /* Set to fast frequency so we do not see flashing */ + pca955x_write_psc(client, 0, 0); + pca955x_write_psc(client, 1, 0); + + return 0; +exit: + return err; +} + +static int __devexit pca955x_remove(struct i2c_client *client) +{ + struct pca955x_led *pca955x = i2c_get_clientdata(client); + int leds = pca955x->chipdef->bits; + int i; + + for (i = 0; i < leds; i++) { + led_classdev_unregister(&(pca955x->led_cdev)); + cancel_work_sync(&(pca955x->work)); + kfree(pca955x); + pca955x = pca955x + 1; + } + + return 0; +} + +static struct i2c_driver pca955x_driver = { + .driver = { + .name = "leds-pca955x", + .owner = THIS_MODULE, + }, + .probe = pca955x_probe, + .remove = __devexit_p(pca955x_remove), + .id_table = pca955x_id, +}; + +static int __init pca955x_leds_init(void) +{ + return i2c_add_driver(&pca955x_driver); +} + +static void __exit pca955x_leds_exit(void) +{ + i2c_del_driver(&pca955x_driver); +} + +module_init(pca955x_leds_init); +module_exit(pca955x_leds_exit); + +MODULE_AUTHOR("Nate Case "); +MODULE_DESCRIPTION("PCA955x LED driver"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/leds.h b/include/linux/leds.h index e7a5e89932fe..d41ccb56146a 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -118,6 +118,20 @@ extern void ledtrig_ide_activity(void); #define ledtrig_ide_activity() do {} while(0) #endif +/* + * Generic LED platform data for describing LED names and default triggers. + */ +struct led_info { + const char *name; + char *default_trigger; + int flags; +}; + +struct led_platform_data { + int num_leds; + struct led_info *leds; +}; + /* For the leds-gpio driver */ struct gpio_led { const char *name; -- cgit v1.2.3-58-ga151