misc: led: Add PCA9551 LED driver

This patch adds a driver for the PCA9551 LED controller.

Originated-by: Timo Herbrecher <t.herbrecher@gateware.de>
Signed-off-by: Stefan Roese <sr@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
Cc: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Fabio Estevam <fabio.estevam@freescale.com>

diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 0e571d91ea8c31f1311926eb02e41c0d9c5ea4dc..64b07a30155b6622349e611c9d6eaecd443fb244 100644 (file)
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -60,3 +60,16 @@ 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 25630c3f2b42cbd30508fa171ad8cd4f11928a96..120babc4b5d87e2ac344f96d1f4849f6de80ce54 100644 (file)
--- 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 (file)
index 0000000..79b1e20
--- /dev/null
+++ b/drivers/misc/pca9551_led.c
@@ -0,0 +1,155 @@
+/*
+ * Copyright (C) 2015 Stefan Roese <sr@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);
+}