[U-Boot] [PATCH v2] misc: led: Add PCA9551 LED driver
Stefan Roese
sr at denx.de
Thu Mar 12 11:22:46 CET 2015
This patch adds a driver for the PCA9551 LED controller.
Originated-by: Timo Herbrecher <t.herbrecher at gateware.de>
Signed-off-by: Stefan Roese <sr at denx.de>
Reviewed-by: Tom Rini <trini at konsulko.com>
Cc: Fabio Estevam <festevam at gmail.com>
---
v2:
- Removed __packed fromstruct pca9551_blink_rate as it doesn't seem to be
needed
- Removed PCA9551 dependency from Kconfig to allow usage with other boards
- Better handling of return codes as suggested by Fabio
drivers/misc/Kconfig | 13 ++++
drivers/misc/Makefile | 1 +
drivers/misc/pca9551_led.c | 155 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 169 insertions(+)
create mode 100644 drivers/misc/pca9551_led.c
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 36a8f0d..4114be3 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -61,3 +61,16 @@ config CONFIG_FSL_SEC_MON
system states.
Security Monitor can be transitioned on any security failures,
like software violations or hardware security violations.
+
+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 6028cd4..149e686 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -29,3 +29,4 @@ obj-$(CONFIG_STATUS_LED) += status_led.o
obj-$(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 0000000..79b1e20
--- /dev/null
+++ b/drivers/misc/pca9551_led.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2015 Stefan Roese <sr at denx.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <i2c.h>
+
+#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);
+}
--
2.3.2
More information about the U-Boot
mailing list