From 352b296d30df06b880d2c7620910cd759dc2609d Mon Sep 17 00:00:00 2001 From: Samuel Holland Date: Sat, 26 Jun 2021 11:02:49 -0500 Subject: [PATCH 055/117] leds: sun50i-a100: New driver for the A100 LED controller Some Allwinner sunxi SoCs, starting with the A100, contain an LED controller designed to drive RGB LED pixels. Add a driver for it using the multicolor LED framework, and with LEDs defined in the device tree. Series-changes: 2 - Renamed from sunxi-ledc to sun50i-r329-ledc - Added missing "static" to functions/globals as reported by 0day bot Series-changes: 3 - Added vendor prefix to timing/format properties - Renamed "format" property to "pixel-format" for clarity - Dropped "vled-supply" as it is unrelated to the controller hardware - Changed "writesl" to "iowrite32_rep" so the driver builds on hppa Series-changes: 4 - Depend on LEDS_CLASS_MULTICOLOR Series-changes: 5 - Rename the driver R329 -> A100, since that is the actual original implementation Signed-off-by: Samuel Holland --- drivers/leds/Kconfig | 9 + drivers/leds/Makefile | 1 + drivers/leds/leds-sun50i-a100.c | 554 ++++++++++++++++++++++++++++++++ 3 files changed, 564 insertions(+) create mode 100644 drivers/leds/leds-sun50i-a100.c --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -283,6 +283,15 @@ config LEDS_COBALT_RAQ help This option enables support for the Cobalt Raq series LEDs. +config LEDS_SUN50I_A100 + tristate "LED support for Allwinner A100 RGB LED controller" + depends on LEDS_CLASS_MULTICOLOR && OF + depends on ARCH_SUNXI || COMPILE_TEST + help + This option enables support for the RGB LED controller found + in some Allwinner sunxi SoCs, includeing A100, R329, and D1. + It uses a one-wire interface to control up to 1024 LEDs. + config LEDS_SUNFIRE tristate "LED support for SunFire servers." depends on LEDS_CLASS --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_LEDS_PWM) += leds-pwm.o obj-$(CONFIG_LEDS_REGULATOR) += leds-regulator.o obj-$(CONFIG_LEDS_S3C24XX) += leds-s3c24xx.o obj-$(CONFIG_LEDS_SC27XX_BLTC) += leds-sc27xx-bltc.o +obj-$(CONFIG_LEDS_SUN50I_A100) += leds-sun50i-a100.o obj-$(CONFIG_LEDS_SUNFIRE) += leds-sunfire.o obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o obj-$(CONFIG_LEDS_TCA6507) += leds-tca6507.o --- /dev/null +++ b/drivers/leds/leds-sun50i-a100.c @@ -0,0 +1,554 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright (c) 2021-2022 Samuel Holland +// +// Partly based on drivers/leds/leds-turris-omnia.c, which is: +// Copyright (c) 2020 by Marek Behún +// + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define LEDC_CTRL_REG 0x0000 +#define LEDC_CTRL_REG_DATA_LENGTH (0x1fff << 16) +#define LEDC_CTRL_REG_RGB_MODE (0x7 << 6) +#define LEDC_CTRL_REG_LEDC_EN BIT(0) +#define LEDC_T01_TIMING_CTRL_REG 0x0004 +#define LEDC_T01_TIMING_CTRL_REG_T1H (0x3f << 21) +#define LEDC_T01_TIMING_CTRL_REG_T1L (0x1f << 16) +#define LEDC_T01_TIMING_CTRL_REG_T0H (0x1f << 6) +#define LEDC_T01_TIMING_CTRL_REG_T0L (0x3f << 0) +#define LEDC_RESET_TIMING_CTRL_REG 0x000c +#define LEDC_RESET_TIMING_CTRL_REG_LED_NUM (0x3ff << 0) +#define LEDC_DATA_REG 0x0014 +#define LEDC_DMA_CTRL_REG 0x0018 +#define LEDC_DMA_CTRL_REG_FIFO_TRIG_LEVEL (0x1f << 0) +#define LEDC_INT_CTRL_REG 0x001c +#define LEDC_INT_CTRL_REG_GLOBAL_INT_EN BIT(5) +#define LEDC_INT_CTRL_REG_FIFO_CPUREQ_INT_EN BIT(1) +#define LEDC_INT_CTRL_REG_TRANS_FINISH_INT_EN BIT(0) +#define LEDC_INT_STS_REG 0x0020 +#define LEDC_INT_STS_REG_FIFO_CPUREQ_INT BIT(1) +#define LEDC_INT_STS_REG_TRANS_FINISH_INT BIT(0) + +#define LEDC_FIFO_DEPTH 32 +#define LEDC_MAX_LEDS 1024 + +#define LEDS_TO_BYTES(n) ((n) * sizeof(u32)) + +struct sun50i_a100_ledc_led { + struct led_classdev_mc mc_cdev; + struct mc_subled subled_info[3]; +}; + +#define to_ledc_led(mc) container_of(mc, struct sun50i_a100_ledc_led, mc_cdev) + +struct sun50i_a100_ledc_timing { + u32 t0h_ns; + u32 t0l_ns; + u32 t1h_ns; + u32 t1l_ns; + u32 treset_ns; +}; + +struct sun50i_a100_ledc { + struct device *dev; + void __iomem *base; + struct clk *bus_clk; + struct clk *mod_clk; + struct reset_control *reset; + + u32 *buffer; + struct dma_chan *dma_chan; + dma_addr_t dma_handle; + int pio_length; + int pio_offset; + + spinlock_t lock; + int next_length; + bool xfer_active; + + u32 format; + struct sun50i_a100_ledc_timing timing; + + int num_leds; + struct sun50i_a100_ledc_led leds[]; +}; + +static int sun50i_a100_ledc_dma_xfer(struct sun50i_a100_ledc *priv, int length) +{ + struct dma_async_tx_descriptor *desc; + dma_cookie_t cookie; + + desc = dmaengine_prep_slave_single(priv->dma_chan, priv->dma_handle, + LEDS_TO_BYTES(length), + DMA_MEM_TO_DEV, 0); + if (!desc) + return -ENOMEM; + + cookie = dmaengine_submit(desc); + if (dma_submit_error(cookie)) + return -EIO; + + dma_async_issue_pending(priv->dma_chan); + + return 0; +} + +static void sun50i_a100_ledc_pio_xfer(struct sun50i_a100_ledc *priv, int length) +{ + u32 burst, offset, val; + + if (length) { + /* New transfer (FIFO is empty). */ + offset = 0; + burst = min(length, LEDC_FIFO_DEPTH); + } else { + /* Existing transfer (FIFO is half-full). */ + length = priv->pio_length; + offset = priv->pio_offset; + burst = min(length, LEDC_FIFO_DEPTH / 2); + } + + iowrite32_rep(priv->base + LEDC_DATA_REG, priv->buffer + offset, burst); + + if (burst < length) { + priv->pio_length = length - burst; + priv->pio_offset = offset + burst; + + if (!offset) { + val = readl(priv->base + LEDC_INT_CTRL_REG); + val |= LEDC_INT_CTRL_REG_FIFO_CPUREQ_INT_EN; + writel(val, priv->base + LEDC_INT_CTRL_REG); + } + } else { + /* Disable the request IRQ once all data is written. */ + val = readl(priv->base + LEDC_INT_CTRL_REG); + val &= ~LEDC_INT_CTRL_REG_FIFO_CPUREQ_INT_EN; + writel(val, priv->base + LEDC_INT_CTRL_REG); + } +} + +static void sun50i_a100_ledc_start_xfer(struct sun50i_a100_ledc *priv, + int length) +{ + u32 val; + + dev_dbg(priv->dev, "Updating %d LEDs\n", length); + + val = readl(priv->base + LEDC_CTRL_REG); + val &= ~LEDC_CTRL_REG_DATA_LENGTH; + val |= length << 16 | LEDC_CTRL_REG_LEDC_EN; + writel(val, priv->base + LEDC_CTRL_REG); + + if (length > LEDC_FIFO_DEPTH) { + int ret = sun50i_a100_ledc_dma_xfer(priv, length); + + if (!ret) + return; + + dev_warn(priv->dev, "Failed to set up DMA: %d\n", ret); + } + + sun50i_a100_ledc_pio_xfer(priv, length); +} + +static irqreturn_t sun50i_a100_ledc_irq(int irq, void *dev_id) +{ + struct sun50i_a100_ledc *priv = dev_id; + u32 val; + + val = readl(priv->base + LEDC_INT_STS_REG); + + if (val & LEDC_INT_STS_REG_TRANS_FINISH_INT) { + int next_length; + + /* Start the next transfer if needed. */ + spin_lock(&priv->lock); + next_length = priv->next_length; + if (next_length) + priv->next_length = 0; + else + priv->xfer_active = false; + spin_unlock(&priv->lock); + + if (next_length) + sun50i_a100_ledc_start_xfer(priv, next_length); + } else if (val & LEDC_INT_STS_REG_FIFO_CPUREQ_INT) { + /* Continue the current transfer. */ + sun50i_a100_ledc_pio_xfer(priv, 0); + } + + writel(val, priv->base + LEDC_INT_STS_REG); + + return IRQ_HANDLED; +} + +static void sun50i_a100_ledc_brightness_set(struct led_classdev *cdev, + enum led_brightness brightness) +{ + struct sun50i_a100_ledc *priv = dev_get_drvdata(cdev->dev->parent); + struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev); + struct sun50i_a100_ledc_led *led = to_ledc_led(mc_cdev); + int addr = led - priv->leds; + unsigned long flags; + bool xfer_active; + int next_length; + + led_mc_calc_color_components(mc_cdev, brightness); + + priv->buffer[addr] = led->subled_info[0].brightness << 16 | + led->subled_info[1].brightness << 8 | + led->subled_info[2].brightness; + + dev_dbg(priv->dev, "LED %d -> #%06x\n", addr, priv->buffer[addr]); + + spin_lock_irqsave(&priv->lock, flags); + next_length = max(priv->next_length, addr + 1); + xfer_active = priv->xfer_active; + if (xfer_active) + priv->next_length = next_length; + else + priv->xfer_active = true; + spin_unlock_irqrestore(&priv->lock, flags); + + if (!xfer_active) + sun50i_a100_ledc_start_xfer(priv, next_length); +} + +static const char *const sun50i_a100_ledc_formats[] = { + "rgb", + "rbg", + "grb", + "gbr", + "brg", + "bgr", +}; + +static int sun50i_a100_ledc_parse_format(const struct device_node *np, + struct sun50i_a100_ledc *priv) +{ + const char *format = "grb"; + u32 i; + + of_property_read_string(np, "allwinner,pixel-format", &format); + + for (i = 0; i < ARRAY_SIZE(sun50i_a100_ledc_formats); ++i) { + if (!strcmp(format, sun50i_a100_ledc_formats[i])) { + priv->format = i; + return 0; + } + } + + dev_err(priv->dev, "Bad pixel format '%s'\n", format); + + return -EINVAL; +} + +static void sun50i_a100_ledc_set_format(struct sun50i_a100_ledc *priv) +{ + u32 val; + + val = readl(priv->base + LEDC_CTRL_REG); + val &= ~LEDC_CTRL_REG_RGB_MODE; + val |= priv->format << 6; + writel(val, priv->base + LEDC_CTRL_REG); +} + +static const struct sun50i_a100_ledc_timing sun50i_a100_ledc_default_timing = { + .t0h_ns = 336, + .t0l_ns = 840, + .t1h_ns = 882, + .t1l_ns = 294, + .treset_ns = 300000, +}; + +static int sun50i_a100_ledc_parse_timing(const struct device_node *np, + struct sun50i_a100_ledc *priv) +{ + struct sun50i_a100_ledc_timing *timing = &priv->timing; + + *timing = sun50i_a100_ledc_default_timing; + + of_property_read_u32(np, "allwinner,t0h-ns", &timing->t0h_ns); + of_property_read_u32(np, "allwinner,t0l-ns", &timing->t0l_ns); + of_property_read_u32(np, "allwinner,t1h-ns", &timing->t1h_ns); + of_property_read_u32(np, "allwinner,t1l-ns", &timing->t1l_ns); + of_property_read_u32(np, "allwinner,treset-ns", &timing->treset_ns); + + return 0; +} + +static void sun50i_a100_ledc_set_timing(struct sun50i_a100_ledc *priv) +{ + const struct sun50i_a100_ledc_timing *timing = &priv->timing; + unsigned long mod_freq = clk_get_rate(priv->mod_clk); + u32 cycle_ns = NSEC_PER_SEC / mod_freq; + u32 val; + + val = (timing->t1h_ns / cycle_ns) << 21 | + (timing->t1l_ns / cycle_ns) << 16 | + (timing->t0h_ns / cycle_ns) << 6 | + (timing->t0l_ns / cycle_ns); + writel(val, priv->base + LEDC_T01_TIMING_CTRL_REG); + + val = (timing->treset_ns / cycle_ns) << 16 | + (priv->num_leds - 1); + writel(val, priv->base + LEDC_RESET_TIMING_CTRL_REG); +} + +static int sun50i_a100_ledc_resume(struct device *dev) +{ + struct sun50i_a100_ledc *priv = dev_get_drvdata(dev); + u32 val; + int ret; + + ret = reset_control_deassert(priv->reset); + if (ret) + return ret; + + ret = clk_prepare_enable(priv->bus_clk); + if (ret) + goto err_assert_reset; + + ret = clk_prepare_enable(priv->mod_clk); + if (ret) + goto err_disable_bus_clk; + + sun50i_a100_ledc_set_format(priv); + sun50i_a100_ledc_set_timing(priv); + + /* The trigger level must be at least the burst length. */ + val = readl(priv->base + LEDC_DMA_CTRL_REG); + val &= ~LEDC_DMA_CTRL_REG_FIFO_TRIG_LEVEL; + val |= LEDC_FIFO_DEPTH / 2; + writel(val, priv->base + LEDC_DMA_CTRL_REG); + + val = LEDC_INT_CTRL_REG_GLOBAL_INT_EN | + LEDC_INT_CTRL_REG_TRANS_FINISH_INT_EN; + writel(val, priv->base + LEDC_INT_CTRL_REG); + + return 0; + +err_disable_bus_clk: + clk_disable_unprepare(priv->bus_clk); +err_assert_reset: + reset_control_assert(priv->reset); + + return ret; +} + +static int sun50i_a100_ledc_suspend(struct device *dev) +{ + struct sun50i_a100_ledc *priv = dev_get_drvdata(dev); + + clk_disable_unprepare(priv->mod_clk); + clk_disable_unprepare(priv->bus_clk); + reset_control_assert(priv->reset); + + return 0; +} + +static void sun50i_a100_ledc_dma_cleanup(void *data) +{ + struct sun50i_a100_ledc *priv = data; + struct device *dma_dev = dmaengine_get_dma_device(priv->dma_chan); + + if (priv->buffer) + dma_free_wc(dma_dev, LEDS_TO_BYTES(priv->num_leds), + priv->buffer, priv->dma_handle); + dma_release_channel(priv->dma_chan); +} + +static int sun50i_a100_ledc_probe(struct platform_device *pdev) +{ + const struct device_node *np = pdev->dev.of_node; + struct dma_slave_config dma_cfg = {}; + struct led_init_data init_data = {}; + struct device *dev = &pdev->dev; + struct device_node *child; + struct sun50i_a100_ledc *priv; + struct resource *mem; + int count, irq, ret; + + count = of_get_available_child_count(np); + if (!count) + return -ENODEV; + if (count > LEDC_MAX_LEDS) { + dev_err(dev, "Too many LEDs! (max is %d)\n", LEDC_MAX_LEDS); + return -EINVAL; + } + + priv = devm_kzalloc(dev, struct_size(priv, leds, count), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + priv->num_leds = count; + spin_lock_init(&priv->lock); + dev_set_drvdata(dev, priv); + + ret = sun50i_a100_ledc_parse_format(np, priv); + if (ret) + return ret; + + ret = sun50i_a100_ledc_parse_timing(np, priv); + if (ret) + return ret; + + priv->base = devm_platform_get_and_ioremap_resource(pdev, 0, &mem); + if (IS_ERR(priv->base)) + return PTR_ERR(priv->base); + + priv->bus_clk = devm_clk_get(dev, "bus"); + if (IS_ERR(priv->bus_clk)) + return PTR_ERR(priv->bus_clk); + + priv->mod_clk = devm_clk_get(dev, "mod"); + if (IS_ERR(priv->mod_clk)) + return PTR_ERR(priv->mod_clk); + + priv->reset = devm_reset_control_get_exclusive(dev, NULL); + if (IS_ERR(priv->reset)) + return PTR_ERR(priv->reset); + + priv->dma_chan = dma_request_chan(dev, "tx"); + if (IS_ERR(priv->dma_chan)) + return PTR_ERR(priv->dma_chan); + + ret = devm_add_action_or_reset(dev, sun50i_a100_ledc_dma_cleanup, priv); + if (ret) + return ret; + + dma_cfg.dst_addr = mem->start + LEDC_DATA_REG; + dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + dma_cfg.dst_maxburst = LEDC_FIFO_DEPTH / 2; + ret = dmaengine_slave_config(priv->dma_chan, &dma_cfg); + if (ret) + return ret; + + priv->buffer = dma_alloc_wc(dmaengine_get_dma_device(priv->dma_chan), + LEDS_TO_BYTES(priv->num_leds), + &priv->dma_handle, GFP_KERNEL); + if (!priv->buffer) + return -ENOMEM; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return irq; + + ret = devm_request_irq(dev, irq, sun50i_a100_ledc_irq, + 0, dev_name(dev), priv); + if (ret) + return ret; + + ret = sun50i_a100_ledc_resume(dev); + if (ret) + return ret; + + for_each_available_child_of_node(np, child) { + struct sun50i_a100_ledc_led *led; + struct led_classdev *cdev; + u32 addr, color; + + ret = of_property_read_u32(child, "reg", &addr); + if (ret || addr >= count) { + dev_err(dev, "LED 'reg' values must be from 0 to %d\n", + priv->num_leds - 1); + ret = -EINVAL; + goto err_put_child; + } + + ret = of_property_read_u32(child, "color", &color); + if (ret || color != LED_COLOR_ID_RGB) { + dev_err(dev, "LED 'color' must be LED_COLOR_ID_RGB\n"); + ret = -EINVAL; + goto err_put_child; + } + + led = &priv->leds[addr]; + + led->subled_info[0].color_index = LED_COLOR_ID_RED; + led->subled_info[0].channel = 0; + led->subled_info[1].color_index = LED_COLOR_ID_GREEN; + led->subled_info[1].channel = 1; + led->subled_info[2].color_index = LED_COLOR_ID_BLUE; + led->subled_info[2].channel = 2; + + led->mc_cdev.num_colors = ARRAY_SIZE(led->subled_info); + led->mc_cdev.subled_info = led->subled_info; + + cdev = &led->mc_cdev.led_cdev; + cdev->max_brightness = U8_MAX; + cdev->brightness_set = sun50i_a100_ledc_brightness_set; + + init_data.fwnode = of_fwnode_handle(child); + + ret = devm_led_classdev_multicolor_register_ext(dev, + &led->mc_cdev, + &init_data); + if (ret) { + dev_err(dev, "Failed to register LED %u: %d\n", + addr, ret); + goto err_put_child; + } + } + + dev_info(dev, "Registered %d LEDs\n", priv->num_leds); + + return 0; + +err_put_child: + of_node_put(child); + sun50i_a100_ledc_suspend(&pdev->dev); + + return ret; +} + +static int sun50i_a100_ledc_remove(struct platform_device *pdev) +{ + sun50i_a100_ledc_suspend(&pdev->dev); + + return 0; +} + +static void sun50i_a100_ledc_shutdown(struct platform_device *pdev) +{ + sun50i_a100_ledc_suspend(&pdev->dev); +} + +static const struct of_device_id sun50i_a100_ledc_of_match[] = { + { .compatible = "allwinner,sun50i-a100-ledc" }, + {} +}; +MODULE_DEVICE_TABLE(of, sun50i_a100_ledc_of_match); + +static SIMPLE_DEV_PM_OPS(sun50i_a100_ledc_pm, + sun50i_a100_ledc_suspend, sun50i_a100_ledc_resume); + +static struct platform_driver sun50i_a100_ledc_driver = { + .probe = sun50i_a100_ledc_probe, + .remove = sun50i_a100_ledc_remove, + .shutdown = sun50i_a100_ledc_shutdown, + .driver = { + .name = "sun50i-a100-ledc", + .of_match_table = sun50i_a100_ledc_of_match, + .pm = pm_ptr(&sun50i_a100_ledc_pm), + }, +}; +module_platform_driver(sun50i_a100_ledc_driver); + +MODULE_AUTHOR("Samuel Holland "); +MODULE_DESCRIPTION("Allwinner A100 LED controller driver"); +MODULE_LICENSE("GPL");