This patch adds a LED class driver for the RGB LEDs found on
the Crane Merchandising System CR0014114 LEDs board.
Driver creates LED devices with name written using the following
pattern "LABEL-{N}:{red,green,blue}:".
Signed-off-by: Oleh Kravchenko <oleg@xxxxxxxxxx>
---
.../devicetree/bindings/leds/leds-cr0014114.txt | 23 ++
.../devicetree/bindings/vendor-prefixes.txt | 1 +
drivers/leds/Kconfig | 12 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-cr0014114.c | 352 +++++++++++++++++++++
5 files changed, 389 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/leds-cr0014114.txt
create mode 100644 drivers/leds/leds-cr0014114.c
diff --git a/Documentation/devicetree/bindings/leds/leds-cr0014114.txt b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
new file mode 100644
index 000000000000..6a399cb65388
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/leds-cr0014114.txt
@@ -0,0 +1,23 @@
+Crane Merchandising System SPI LED board CR0014114
+==================================================
+
+Required properties:
+- compatible: "cms,cr0014114"
+
+Optional properties:
+- label: prefix for LED names. If omitted the label is taken from the node name.
+- leds-per-board: RGB leds per board, minimal value is 6
+- num-boards: number of LED boards on SPI bus, usually 1
+
+Example
+-------
+
+cr0014114@0 {
+ compatible = "ccs,cr0014114";
+ reg = <0>;
+ spi-max-frequency = <50000>;
+ spi-cpha;
+ label = "cr0014114";
+ leds-per-board = /bits/ 8 <6>;
+ num-boards = /bits/ 8 <1>;
+};
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 7e5754ecb095..ad72b278d307 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -67,6 +67,7 @@ chunghwa Chunghwa Picture Tubes Ltd.
ciaa Computadora Industrial Abierta Argentina
cirrus Cirrus Logic, Inc.
cloudengines Cloud Engines, Inc.
+cms Crane Merchandising System
cnm Chips&Media, Inc.
cnxt Conexant Systems, Inc.
compulab CompuLab Ltd.
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 594b24d410c3..2d1527fc7643 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -76,6 +76,18 @@ config LEDS_BCM6358
This option enables support for LEDs connected to the BCM6358
LED HW controller accessed via MMIO registers.
+config LEDS_CR0014114
+ tristate "LED Support for Crane Merchandising Systems CR0014114"
+ depends on LEDS_CLASS
+ depends on SPI
+ depends on OF
+ help
+ The CR0014114 LED board used in vending machines produced
+ by Crane Merchandising Systems.
+
+ This driver creates LED devices with name written using the
+ following pattern "LABEL-{N}:{red,green,blue}:".
+
config LEDS_CPCAP
tristate "LED Support for Motorola CPCAP"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 909dae62ba05..fd886a30267d 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -73,6 +73,7 @@ obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o
obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o
# LED SPI Drivers
+obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o
obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o
# LED Userspace Drivers
diff --git a/drivers/leds/leds-cr0014114.c b/drivers/leds/leds-cr0014114.c
new file mode 100644
index 000000000000..490ee3996a5d
--- /dev/null
+++ b/drivers/leds/leds-cr0014114.c
@@ -0,0 +1,352 @@
+#include <linux/delay.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/property.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/workqueue.h>
+
+/* CR0014114 SPI commands */
+#define CMD_SET_BRIGHTNESS 0x80
+#define CMD_INIT_REENUMERATE 0x81
+#define CMD_NEXT_REENUMERATE 0x82
+
+/* default settings */
+#define DEF_LEDS_PER_BOARD 6
+#define DEF_MAX_BRIGHTNESS GENMASK(6, 0)
+#define DEF_NUM_BOARDS 1
+#define DEF_FPS 50
+#define DEF_FW_DELAY_MSEC 10
+#define DEF_RECOUNT_DELAY (HZ * 3600)
+
+struct cr0014114 {
+ struct spi_device *spi;
+ struct device *dev;
+ const char *label;
+ u8 leds_per_board;
+ u8 num_boards;
+ size_t leds_count;
+ char wq_name[64];
+ struct workqueue_struct *wq;
+ unsigned long leds_delay;
+ struct work_struct leds_work;
+ struct timer_list recount_timer;
+ struct work_struct recount_work;
+ struct cr0014114_led *leds;
+};
+
+struct cr0014114_led {
+ char name[64];
+ struct cr0014114 *priv;
+ struct led_classdev ldev;
+ u8 brightness;
+};
+
+static void cr0014114_calc_crc(u8 *buf, const size_t len)
+{
+ u8 crc;
+ size_t i;
+
+ for (i = 1, crc = 1; i < len - 1; i++)
+ crc += buf[i];
+
+ crc |= BIT(7);
+
+ /* special case when CRC matches to SPI commands */
+ switch (crc) {
+ case CMD_SET_BRIGHTNESS:
+ case CMD_INIT_REENUMERATE:
+ case CMD_NEXT_REENUMERATE:
+ crc = 0xfe;
+ break;
+ }
+
+ buf[len - 1] = crc;
+}
+
+static void cr0014114_leds_work(struct work_struct *work)
+{
+ int ret;
+ size_t i;
+ struct cr0014114 *priv = container_of(work,
+ struct cr0014114, leds_work);
+ u8 data[priv->leds_count + 2];
+ unsigned long udelay, now = jiffies;
+
+ /* to avoid SPI mistiming with firmware we should wait some time */
+ if (time_after(priv->leds_delay, now)) {
+ udelay = jiffies_to_usecs(priv->leds_delay - now);
+ usleep_range(udelay, udelay + 1);
+ }
+
+ data[0] = CMD_SET_BRIGHTNESS;
+ for (i = 0; i < priv->leds_count; i++)
+ data[i + 1] = priv->leds[i].brightness;
+ cr0014114_calc_crc(data, sizeof(data));
+
+ ret = spi_write(priv->spi, data, sizeof(data));
+ if (ret)
+ dev_err(priv->dev, "spi_write() error %d\n", ret);
+
+ priv->leds_delay = jiffies + msecs_to_jiffies(DEF_FW_DELAY_MSEC);
+}
+
+static void cr0014114_test(struct cr0014114 *priv)
+{
+ unsigned int mdelay;
+ size_t i;
+ struct led_classdev *ldev;
+
+ /* blink all LEDs in 500 milliseconds */
+ mdelay = 500 / priv->leds_count - DEF_FW_DELAY_MSEC;
+ if (mdelay < DEF_FW_DELAY_MSEC)
+ mdelay = DEF_FW_DELAY_MSEC;
+
+ for (i = 0; i < priv->leds_count; i++) {
+ ldev = &priv->leds[i].ldev;
+
+ ldev->brightness_set(ldev, DEF_MAX_BRIGHTNESS);
+ msleep(mdelay);
+ ldev->brightness_set(ldev, LED_OFF);
+ }
+}
+
+static void cr0014114_set_brightness(struct led_classdev *ldev,
+ enum led_brightness brightness)
+{
+ struct cr0014114_led *led = container_of(ldev,
+ struct cr0014114_led, ldev);
+
+ led->brightness = brightness & DEF_MAX_BRIGHTNESS;
+ queue_work(led->priv->wq, &led->priv->leds_work);
+}
+
+static int cr0014114_led_create(struct cr0014114 *priv,
+ struct cr0014114_led *led,
+ size_t id,
+ const char *color)
+{
+ int ret;
+
+ led->priv = priv;
+ snprintf(led->name, sizeof(led->name), "%s-%zd:%s:",
+ priv->label, id, color);
+
+ led->ldev.name = led->name;
+ led->ldev.brightness = LED_OFF;
+ led->ldev.max_brightness = DEF_MAX_BRIGHTNESS;
+ led->ldev.brightness_set = cr0014114_set_brightness;
+
+ ret = led_classdev_register(priv->dev, &led->ldev);
+ if (ret)
+ dev_err(priv->dev, "can't register LED '%s', error %d\n",
+ led->name, ret);
+
+ return ret;
+}
+
+static int cr0014114_recount(struct cr0014114 *priv)
+{
+ size_t i;
+ int ret;
+ u8 cmd_init = CMD_INIT_REENUMERATE;
+ u8 cmd_next = CMD_NEXT_REENUMERATE;
+
+ dev_dbg(priv->dev, "recount of LEDs is started\n");
+
+ msleep(DEF_FW_DELAY_MSEC);
+
+ ret = spi_write(priv->spi, &cmd_init, sizeof(cmd_init));
+ if (ret)
+ return ret;
+
+ for (i = 0; i < priv->leds_count; i++) {
+ msleep(DEF_FW_DELAY_MSEC);
+
+ ret = spi_write(priv->spi, &cmd_next, sizeof(cmd_next));
+ if (ret)
+ return ret;
+ }
+
+ priv->leds_delay = jiffies + msecs_to_jiffies(DEF_FW_DELAY_MSEC);
+
+ dev_dbg(priv->dev, "recount of LEDs is complete\n");
+
+ return 0;
+}
+
+void cr0014114_recount_timer(unsigned long data)
+{
+ struct cr0014114 *priv = (struct cr0014114 *)data;
+
+ queue_work(priv->wq, &priv->recount_work);
+ mod_timer(&priv->recount_timer, jiffies + DEF_RECOUNT_DELAY);
+}
+
+static void cr0014114_recount_work(struct work_struct *work)
+{
+ struct cr0014114 *priv = container_of(work, struct cr0014114,
+ recount_work);
+
+ cr0014114_recount(priv);
+
+ /* after recount we should restore brightness */
+ queue_work(priv->wq, &priv->leds_work);
+}
+
+static int cr0014114_probe_dp(struct cr0014114 *priv)
+{
+ if (device_property_read_string(priv->dev, "label", &priv->label))
+ priv->label = priv->dev->of_node->name;
+ if (!priv->label || !*priv->label) {
+ dev_err(priv->dev, "'label' can't be empty\n");
+ return -EINVAL;
+ }
+
+ if (device_property_read_u8(priv->dev, "leds-per-board",
+ &priv->leds_per_board))
+ priv->leds_per_board = DEF_LEDS_PER_BOARD;
+ if (priv->leds_per_board < DEF_LEDS_PER_BOARD) {
+ dev_err(priv->dev,
+ "'leds-per-board' should be at least %d\n",
+ DEF_LEDS_PER_BOARD
+ );
+ return -EINVAL;
+ }
+
+ if (device_property_read_u8(priv->dev, "num-boards",
+ &priv->num_boards))
+ priv->num_boards = DEF_NUM_BOARDS;
+ if (priv->num_boards < DEF_NUM_BOARDS) {
+ dev_err(priv->dev, "'num-boards' should be at least %d\n",
+ DEF_NUM_BOARDS
+ );
+ return -EINVAL;
+ }
+
+ priv->leds_count = priv->leds_per_board * priv->num_boards * 3;
+ priv->leds = devm_kzalloc(priv->dev, sizeof(*priv->leds) *
+ priv->leds_count, GFP_KERNEL);
+
+ if (!priv->leds)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static int cr0014114_probe(struct spi_device *spi)
+{
+ struct cr0014114 *priv;
+ size_t i, id;
+ int ret;
+
+ priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->spi = spi;
+ priv->dev = &spi->dev;
+ INIT_WORK(&priv->leds_work, cr0014114_leds_work);
+ INIT_WORK(&priv->recount_work, cr0014114_recount_work);
+
+ ret = cr0014114_probe_dp(priv);
+ if (ret)
+ return ret;
+
+ ret = cr0014114_recount(priv);
+ if (ret) {
+ dev_err(priv->dev, "Recount failed with error %d\n", ret);
+
+ return ret;
+ }
+
+ snprintf(priv->wq_name, sizeof(priv->wq_name), "%s/work", priv->label);
+ priv->wq = create_singlethread_workqueue(priv->wq_name);
+ if (!priv->wq)
+ return -ENOMEM;
+
+ i = 0;
+ id = 0;
+
+ while (i < priv->leds_count) {
+ ret = cr0014114_led_create(priv, &priv->leds[i], id, "red");
+ if (ret)
+ goto fail;
+ i++;
+
+ ret = cr0014114_led_create(priv, &priv->leds[i], id, "green");
+ if (ret)
+ goto fail;
+ i++;
+
+ ret = cr0014114_led_create(priv, &priv->leds[i], id, "blue");
+ if (ret)
+ goto fail;
+ i++;
+ id++;
+ }
+
+ cr0014114_test(priv);
+ spi_set_drvdata(spi, priv);
+ setup_timer(&priv->recount_timer, cr0014114_recount_timer,
+ (unsigned long)priv);
+
+ /* setup recount timer to workaround buggy firmware */
+ mod_timer(&priv->recount_timer, jiffies + DEF_RECOUNT_DELAY);
+
+ dev_info(priv->dev,
+ "%s (Boards: %u, LEDs per board: %u, Total channels: %zd)\n",
+ priv->label,
+ priv->num_boards,
+ priv->leds_per_board,
+ priv->leds_count);
+
+ return 0;
+
+fail:
+ while (i--)
+ led_classdev_unregister(&priv->leds[i].ldev);
+
+ destroy_workqueue(priv->wq);
+
+ return ret;
+}
+
+static int cr0014114_remove(struct spi_device *spi)
+{
+ struct cr0014114 *priv = spi_get_drvdata(spi);
+ size_t i;
+
+ for (i = 0; i < priv->leds_count; i++)
+ led_classdev_unregister(&priv->leds[i].ldev);
+
+ del_timer_sync(&priv->recount_timer);
+ destroy_workqueue(priv->wq);
+
+ return 0;
+}
+
+static const struct of_device_id cr0014114_dt_ids[] = {
+ { .compatible = "cms,cr0014114", },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, cr0014114_dt_ids);
+
+static struct spi_driver cr0014114_driver = {
+ .probe = cr0014114_probe,
+ .remove = cr0014114_remove,
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = cr0014114_dt_ids,
+ },
+};
+
+module_spi_driver(cr0014114_driver);
+
+MODULE_AUTHOR("Oleh Kravchenko <oleg@xxxxxxxxxx>");
+MODULE_DESCRIPTION("cr0014114 LED driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:cr0014114");
--
2.13.0
