From: Stefan Roese Date: Thu, 12 Mar 2015 10:22:46 +0000 (+0100) Subject: misc: led: Add PCA9551 LED driver X-Git-Tag: KARO-TX6-2015-09-18~2159 X-Git-Url: https://git.kernelconcepts.de/?p=karo-tx-uboot.git;a=commitdiff_plain;h=9582e10817ba4e0d464a30bb6e9891501f34d9db misc: led: Add PCA9551 LED driver This patch adds a driver for the PCA9551 LED controller. Originated-by: Timo Herbrecher Signed-off-by: Stefan Roese Reviewed-by: Tom Rini Cc: Fabio Estevam Reviewed-by: Fabio Estevam --- diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index 63d093e6d7..13b512158a 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -68,3 +68,16 @@ config MXC_OCOTP config MXS_OCOTP bool "Freescale OCOTP support" depends on SOC_MXS + +config PCA9551_LED + bool "Enable PCA9551 LED driver" + help + Enable driver for PCA9551 LED controller. This controller + is connected via I2C. So I2C needs to be enabled. + +config PCA9551_I2C_ADDR + hex "I2C address of PCA9551 LED controller" + depends on PCA9551_LED + default 0x60 + help + The I2C address of the PCA9551 LED controller. diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index 25630c3f2b..120babc4b5 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -31,3 +31,4 @@ obj-$(CONFIG_SANDBOX) += swap_case.o obj-$(CONFIG_TWL4030_LED) += twl4030_led.o obj-$(CONFIG_FSL_IFC) += fsl_ifc.o obj-$(CONFIG_FSL_SEC_MON) += fsl_sec_mon.o +obj-$(CONFIG_PCA9551_LED) += pca9551_led.o diff --git a/drivers/misc/pca9551_led.c b/drivers/misc/pca9551_led.c new file mode 100644 index 0000000000..79b1e20ccf --- /dev/null +++ b/drivers/misc/pca9551_led.c @@ -0,0 +1,155 @@ +/* + * Copyright (C) 2015 Stefan Roese + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include + +#ifndef CONFIG_PCA9551_I2C_ADDR +#error "CONFIG_PCA9551_I2C_ADDR not defined!" +#endif + +#define PCA9551_REG_INPUT 0x00 /* Input register (read only) */ +#define PCA9551_REG_PSC0 0x01 /* Frequency prescaler 0 */ +#define PCA9551_REG_PWM0 0x02 /* PWM0 */ +#define PCA9551_REG_PSC1 0x03 /* Frequency prescaler 1 */ +#define PCA9551_REG_PWM1 0x04 /* PWM1 */ +#define PCA9551_REG_LS0 0x05 /* LED0 to LED3 selector */ +#define PCA9551_REG_LS1 0x06 /* LED4 to LED7 selector */ + +#define PCA9551_CTRL_AI (1 << 4) /* Auto-increment flag */ + +#define PCA9551_LED_STATE_ON 0x00 +#define PCA9551_LED_STATE_OFF 0x01 +#define PCA9551_LED_STATE_BLINK0 0x02 +#define PCA9551_LED_STATE_BLINK1 0x03 + +struct pca9551_blink_rate { + u8 psc; /* Frequency preescaler, see PCA9551_7.pdf p. 6 */ + u8 pwm; /* Pulse width modulation, see PCA9551_7.pdf p. 6 */ +}; + +static int freq0, freq1; + +static int pca9551_led_get_state(int led, int *state) +{ + unsigned int reg; + u8 shift, buf; + int ret; + + if (led < 0 || led > 7) { + return -EINVAL; + } else if (led < 4) { + reg = PCA9551_REG_LS0; + shift = led << 1; + } else { + reg = PCA9551_REG_LS1; + shift = (led - 4) << 1; + } + + ret = i2c_read(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1); + if (ret) + return ret; + + *state = (buf >> shift) & 0x03; + return 0; +} + +static int pca9551_led_set_state(int led, int state) +{ + unsigned int reg; + u8 shift, buf, mask; + int ret; + + if (led < 0 || led > 7) { + return -EINVAL; + } else if (led < 4) { + reg = PCA9551_REG_LS0; + shift = led << 1; + } else { + reg = PCA9551_REG_LS1; + shift = (led - 4) << 1; + } + mask = 0x03 << shift; + + ret = i2c_read(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1); + if (ret) + return ret; + + buf = (buf & ~mask) | ((state & 0x03) << shift); + + ret = i2c_write(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1); + if (ret) + return ret; + + return 0; +} + +static int pca9551_led_set_blink_rate(int idx, struct pca9551_blink_rate rate) +{ + unsigned int reg; + int ret; + + switch (idx) { + case 0: + reg = PCA9551_REG_PSC0; + break; + case 1: + reg = PCA9551_REG_PSC1; + break; + default: + return -EINVAL; + } + reg |= PCA9551_CTRL_AI; + + ret = i2c_write(CONFIG_PCA9551_I2C_ADDR, reg, 1, (u8 *)&rate, 2); + if (ret) + return ret; + + return 0; +} + +/* + * Functions referenced by cmd_led.c + */ +void __led_set(led_id_t mask, int state) +{ + if (state == STATUS_LED_OFF) + pca9551_led_set_state(mask, PCA9551_LED_STATE_OFF); + else + pca9551_led_set_state(mask, PCA9551_LED_STATE_ON); +} + +void __led_toggle(led_id_t mask) +{ + int state = 0; + + pca9551_led_get_state(mask, &state); + pca9551_led_set_state(mask, !state); +} + +void __led_blink(led_id_t mask, int freq) +{ + struct pca9551_blink_rate rate; + int mode; + int blink; + + if ((freq0 == 0) || (freq == freq0)) { + blink = 0; + mode = PCA9551_LED_STATE_BLINK0; + freq0 = freq; + } else { + blink = 1; + mode = PCA9551_LED_STATE_BLINK1; + freq1 = freq; + } + + rate.psc = ((freq * 38) / 1000) - 1; + rate.pwm = 128; /* 50% duty cycle */ + + pca9551_led_set_blink_rate(blink, rate); + pca9551_led_set_state(mask, mode); +}