leds-lp5521: use generic firmware interface

 LP55xx common driver provides generic firmware interface
 for running a LED pattern.
 LP5521 and LP5523 have many device attributes for running patterns.
 This patch cleans up those complex code.

 Removed device attributes:
 engine1_mode
 engine2_mode
 engine3_mode
 engine1_load
 engine2_load
 engine3_load
 led_pattern

 All device attributes and functions are replaced with two callback functions,
 'firmware_cb' and 'run_engine'.

 New engine functions:
 lp5521_load/stop/run_engine(), lp5521_update_program_memory() and
 lp5521_wait_opmode_done()

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Bryan Wu <cooloney@gmail.com>

1 files changed, 163 insertions, 251 deletions

diff --git a/drivers/leds/leds-lp5521.c b/drivers/leds/leds-lp5521.c
index cec252eae716..89371e065c13 100644
--- a/drivers/leds/leds-lp5521.c
+++ b/drivers/leds/leds-lp5521.c
@@ -35,6 +35,7 @@
 #include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <linux/platform_data/leds-lp55xx.h>
+#include <linux/firmware.h>
 
 #include "leds-lp55xx-common.h"
 
@@ -101,12 +102,28 @@
 /* Reset register value */
 #define LP5521_RESET                    0xFF
 
-struct lp5521_engine {
-        int             id;
-        u8              mode;
-        u8              prog_page;
-        u8              engine_mask;
-};
+/* Program Memory Operations */
+#define LP5521_MODE_R_M                 0x30    /* Operation Mode Register */
+#define LP5521_MODE_G_M                 0x0C
+#define LP5521_MODE_B_M                 0x03
+#define LP5521_LOAD_R                   0x10
+#define LP5521_LOAD_G                   0x04
+#define LP5521_LOAD_B                   0x01
+
+#define LP5521_R_IS_LOADING(mode)       \
+        ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
+#define LP5521_G_IS_LOADING(mode)       \
+        ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
+#define LP5521_B_IS_LOADING(mode)       \
+        ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
+
+#define LP5521_EXEC_R_M                 0x30    /* Enable Register */
+#define LP5521_EXEC_G_M                 0x0C
+#define LP5521_EXEC_B_M                 0x03
+#define LP5521_EXEC_M                   0x3F
+#define LP5521_RUN_R                    0x20
+#define LP5521_RUN_G                    0x08
+#define LP5521_RUN_B                    0x02
 
 struct lp5521_led {
         int                     id;
@@ -122,12 +139,17 @@ struct lp5521_chip {
         struct lp5521_platform_data *pdata;
         struct mutex            lock; /* Serialize control */
         struct i2c_client       *client;
-        struct lp5521_engine    engines[LP5521_MAX_ENGINES];
         struct lp5521_led       leds[LP5521_MAX_LEDS];
         u8                      num_channels;
         u8                      num_leds;
 };
 
+static inline void lp5521_wait_opmode_done(void)
+{
+        /* operation mode change needs to be longer than 153 us */
+        usleep_range(200, 300);
+}
+
 static inline void lp5521_wait_enable_done(void)
 {
         /* it takes more 488 us to update ENABLE register */
@@ -141,23 +163,6 @@ static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
                 led_current);
 }
 
-static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
-{
-        return container_of(cdev, struct lp5521_led, cdev);
-}
-
-static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
-{
-        return container_of(engine, struct lp5521_chip,
-                            engines[engine->id - 1]);
-}
-
-static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
-{
-        return container_of(led, struct lp5521_chip,
-                            leds[led->id]);
-}
-
 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
 {
         return i2c_smbus_write_byte_data(client, reg, value);
@@ -175,65 +180,153 @@ static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
         return 0;
 }
 
-static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
+static void lp5521_load_engine(struct lp55xx_chip *chip)
 {
-        struct lp5521_chip *chip = engine_to_lp5521(engine);
-        struct i2c_client *client = chip->client;
-        int ret;
-        u8 engine_state;
+        enum lp55xx_engine_index idx = chip->engine_idx;
+        u8 mask[] = {
+                [LP55XX_ENGINE_1] = LP5521_MODE_R_M,
+                [LP55XX_ENGINE_2] = LP5521_MODE_G_M,
+                [LP55XX_ENGINE_3] = LP5521_MODE_B_M,
+        };
 
-        /* Only transition between RUN and DIRECT mode are handled here */
-        if (mode == LP5521_CMD_LOAD)
-                return 0;
+        u8 val[] = {
+                [LP55XX_ENGINE_1] = LP5521_LOAD_R,
+                [LP55XX_ENGINE_2] = LP5521_LOAD_G,
+                [LP55XX_ENGINE_3] = LP5521_LOAD_B,
+        };
 
-        if (mode == LP5521_CMD_DISABLED)
-                mode = LP5521_CMD_DIRECT;
+        lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
 
-        ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
-        if (ret < 0)
-                return ret;
+        lp5521_wait_opmode_done();
+}
 
-        /* set mode only for this engine */
-        engine_state &= ~(engine->engine_mask);
-        mode &= engine->engine_mask;
-        engine_state |= mode;
-        return lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
+static void lp5521_stop_engine(struct lp55xx_chip *chip)
+{
+        lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
+        lp5521_wait_opmode_done();
 }
 
-static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
+static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
 {
-        struct lp5521_chip *chip = engine_to_lp5521(eng);
-        struct i2c_client *client = chip->client;
         int ret;
-        int addr;
         u8 mode;
+        u8 exec;
 
-        /* move current engine to direct mode and remember the state */
-        ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
+        /* stop engine */
+        if (!start) {
+                lp5521_stop_engine(chip);
+                lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
+                lp5521_wait_opmode_done();
+                return;
+        }
+
+        /*
+         * To run the engine,
+         * operation mode and enable register should updated at the same time
+         */
+
+        ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
         if (ret)
-                return ret;
+                return;
 
-        /* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
-        usleep_range(1000, 2000);
-        ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
+        ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
         if (ret)
-                return ret;
+                return;
+
+        /* change operation mode to RUN only when each engine is loading */
+        if (LP5521_R_IS_LOADING(mode)) {
+                mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
+                exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
+        }
+
+        if (LP5521_G_IS_LOADING(mode)) {
+                mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
+                exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
+        }
+
+        if (LP5521_B_IS_LOADING(mode)) {
+                mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
+                exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
+        }
+
+        lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
+        lp5521_wait_opmode_done();
 
-        /* For loading, all the engines to load mode */
-        lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
-        /* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
-        usleep_range(1000, 2000);
-        lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
-        /* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
-        usleep_range(1000, 2000);
-
-        addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
-        i2c_smbus_write_i2c_block_data(client,
-                                addr,
-                                LP5521_PROG_MEM_SIZE,
-                                pattern);
-
-        return lp5521_write(client, LP5521_REG_OP_MODE, mode);
+        lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
+        lp5521_wait_enable_done();
+}
+
+static int lp5521_update_program_memory(struct lp55xx_chip *chip,
+                                        const u8 *data, size_t size)
+{
+        enum lp55xx_engine_index idx = chip->engine_idx;
+        u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
+        u8 addr[] = {
+                [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
+                [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
+                [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
+        };
+        unsigned cmd;
+        char c[3];
+        int program_size;
+        int nrchars;
+        int offset = 0;
+        int ret;
+        int i;
+
+        /* clear program memory before updating */
+        for (i = 0; i < LP5521_PROGRAM_LENGTH; i++)
+                lp55xx_write(chip, addr[idx] + i, 0);
+
+        i = 0;
+        while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
+                /* separate sscanfs because length is working only for %s */
+                ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
+                if (ret != 1)
+                        goto err;
+
+                ret = sscanf(c, "%2x", &cmd);
+                if (ret != 1)
+                        goto err;
+
+                pattern[i] = (u8)cmd;
+                offset += nrchars;
+                i++;
+        }
+
+        /* Each instruction is 16bit long. Check that length is even */
+        if (i % 2)
+                goto err;
+
+        program_size = i;
+        for (i = 0; i < program_size; i++)
+                lp55xx_write(chip, addr[idx] + i, pattern[i]);
+
+        return 0;
+
+err:
+        dev_err(&chip->cl->dev, "wrong pattern format\n");
+        return -EINVAL;
+}
+
+static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
+{
+        const struct firmware *fw = chip->fw;
+
+        if (fw->size > LP5521_PROGRAM_LENGTH) {
+                dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
+                        fw->size);
+                return;
+        }
+
+        /*
+         * Program momery sequence
+         *  1) set engine mode to "LOAD"
+         *  2) write firmware data into program memory
+         */
+
+        lp5521_load_engine(chip);
+        lp5521_update_program_memory(chip, fw->data, fw->size);
 }
 
 static int lp5521_post_init_device(struct lp55xx_chip *chip)
@@ -313,155 +406,6 @@ static void lp5521_led_brightness_work(struct work_struct *work)
         mutex_unlock(&chip->lock);
 }
 
-/* Set engine mode and create appropriate sysfs attributes, if required. */
-static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
-{
-        int ret = 0;
-
-        /* if in that mode already do nothing, except for run */
-        if (mode == engine->mode && mode != LP5521_CMD_RUN)
-                return 0;
-
-        if (mode == LP5521_CMD_RUN) {
-                ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
-        } else if (mode == LP5521_CMD_LOAD) {
-                lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
-                lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
-        } else if (mode == LP5521_CMD_DISABLED) {
-                lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
-        }
-
-        engine->mode = mode;
-
-        return ret;
-}
-
-static int lp5521_do_store_load(struct lp5521_engine *engine,
-                                const char *buf, size_t len)
-{
-        struct lp5521_chip *chip = engine_to_lp5521(engine);
-        struct i2c_client *client = chip->client;
-        int  ret, nrchars, offset = 0, i = 0;
-        char c[3];
-        unsigned cmd;
-        u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
-
-        while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
-                /* separate sscanfs because length is working only for %s */
-                ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
-                if (ret != 2)
-                        goto fail;
-                ret = sscanf(c, "%2x", &cmd);
-                if (ret != 1)
-                        goto fail;
-                pattern[i] = (u8)cmd;
-
-                offset += nrchars;
-                i++;
-        }
-
-        /* Each instruction is 16bit long. Check that length is even */
-        if (i % 2)
-                goto fail;
-
-        mutex_lock(&chip->lock);
-        if (engine->mode == LP5521_CMD_LOAD)
-                ret = lp5521_load_program(engine, pattern);
-        else
-                ret = -EINVAL;
-        mutex_unlock(&chip->lock);
-
-        if (ret) {
-                dev_err(&client->dev, "failed loading pattern\n");
-                return ret;
-        }
-
-        return len;
-fail:
-        dev_err(&client->dev, "wrong pattern format\n");
-        return -EINVAL;
-}
-
-static ssize_t store_engine_load(struct device *dev,
-                                     struct device_attribute *attr,
-                                     const char *buf, size_t len, int nr)
-{
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lp5521_chip *chip = i2c_get_clientdata(client);
-        return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
-}
-
-#define store_load(nr)                                                  \
-static ssize_t store_engine##nr##_load(struct device *dev,              \
-                                     struct device_attribute *attr,     \
-                                     const char *buf, size_t len)       \
-{                                                                       \
-        return store_engine_load(dev, attr, buf, len, nr);              \
-}
-store_load(1)
-store_load(2)
-store_load(3)
-
-static ssize_t show_engine_mode(struct device *dev,
-                                struct device_attribute *attr,
-                                char *buf, int nr)
-{
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lp5521_chip *chip = i2c_get_clientdata(client);
-        switch (chip->engines[nr - 1].mode) {
-        case LP5521_CMD_RUN:
-                return sprintf(buf, "run\n");
-        case LP5521_CMD_LOAD:
-                return sprintf(buf, "load\n");
-        case LP5521_CMD_DISABLED:
-                return sprintf(buf, "disabled\n");
-        default:
-                return sprintf(buf, "disabled\n");
-        }
-}
-
-#define show_mode(nr)                                                   \
-static ssize_t show_engine##nr##_mode(struct device *dev,               \
-                                    struct device_attribute *attr,      \
-                                    char *buf)                          \
-{                                                                       \
-        return show_engine_mode(dev, attr, buf, nr);                    \
-}
-show_mode(1)
-show_mode(2)
-show_mode(3)
-
-static ssize_t store_engine_mode(struct device *dev,
-                                 struct device_attribute *attr,
-                                 const char *buf, size_t len, int nr)
-{
-        struct i2c_client *client = to_i2c_client(dev);
-        struct lp5521_chip *chip = i2c_get_clientdata(client);
-        struct lp5521_engine *engine = &chip->engines[nr - 1];
-        mutex_lock(&chip->lock);
-
-        if (!strncmp(buf, "run", 3))
-                lp5521_set_mode(engine, LP5521_CMD_RUN);
-        else if (!strncmp(buf, "load", 4))
-                lp5521_set_mode(engine, LP5521_CMD_LOAD);
-        else if (!strncmp(buf, "disabled", 8))
-                lp5521_set_mode(engine, LP5521_CMD_DISABLED);
-
-        mutex_unlock(&chip->lock);
-        return len;
-}
-
-#define store_mode(nr)                                                  \
-static ssize_t store_engine##nr##_mode(struct device *dev,              \
-                                     struct device_attribute *attr,     \
-                                     const char *buf, size_t len)       \
-{                                                                       \
-        return store_engine_mode(dev, attr, buf, len, nr);              \
-}
-store_mode(1)
-store_mode(2)
-store_mode(3)
-
 static ssize_t lp5521_selftest(struct device *dev,
                                struct device_attribute *attr,
                                char *buf)
@@ -550,45 +494,11 @@ static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip)
         }
 }
 
-static ssize_t store_led_pattern(struct device *dev,
-                                struct device_attribute *attr,
-                                const char *buf, size_t len)
-{
-        struct lp5521_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
-        unsigned long val;
-        int ret;
-
-        ret = kstrtoul(buf, 16, &val);
-        if (ret)
-                return ret;
-
-        lp5521_run_led_pattern(val, chip);
-
-        return len;
-}
-
 /* device attributes */
-static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
-                   show_engine1_mode, store_engine1_mode);
-static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
-                   show_engine2_mode, store_engine2_mode);
-static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
-                   show_engine3_mode, store_engine3_mode);
-static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
-static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
-static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
-static DEVICE_ATTR(led_pattern, S_IWUSR, NULL, store_led_pattern);
 
 static struct attribute *lp5521_attributes[] = {
-        &dev_attr_engine1_mode.attr,
-        &dev_attr_engine2_mode.attr,
-        &dev_attr_engine3_mode.attr,
         &dev_attr_selftest.attr,
-        &dev_attr_engine1_load.attr,
-        &dev_attr_engine2_load.attr,
-        &dev_attr_engine3_load.attr,
-        &dev_attr_led_pattern.attr,
         NULL
 };
 
@@ -623,6 +533,8 @@ static struct lp55xx_device_config lp5521_cfg = {
         .post_init_device   = lp5521_post_init_device,
         .brightness_work_fn = lp5521_led_brightness_work,
         .set_led_current    = lp5521_set_led_current,
+        .firmware_cb        = lp5521_firmware_loaded,
+        .run_engine         = lp5521_run_engine,
 };
 
 static int lp5521_probe(struct i2c_client *client,