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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 18:50:03 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 18:50:03 +0000 |
commit | 01a69402cf9d38ff180345d55c2ee51c7e89fbc7 (patch) | |
tree | b406c5242a088c4f59c6e4b719b783f43aca6ae9 /drivers/leds/leds-sun50i-a100.c | |
parent | Adding upstream version 6.7.12. (diff) | |
download | linux-01a69402cf9d38ff180345d55c2ee51c7e89fbc7.tar.xz linux-01a69402cf9d38ff180345d55c2ee51c7e89fbc7.zip |
Adding upstream version 6.8.9.upstream/6.8.9
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/leds/leds-sun50i-a100.c')
-rw-r--r-- | drivers/leds/leds-sun50i-a100.c | 584 |
1 files changed, 584 insertions, 0 deletions
diff --git a/drivers/leds/leds-sun50i-a100.c b/drivers/leds/leds-sun50i-a100.c new file mode 100644 index 0000000000..62d21c3a35 --- /dev/null +++ b/drivers/leds/leds-sun50i-a100.c @@ -0,0 +1,584 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021-2023 Samuel Holland <samuel@sholland.org> + * + * Partly based on drivers/leds/leds-turris-omnia.c, which is: + * Copyright (c) 2020 by Marek BehĂșn <kabel@kernel.org> + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/dmaengine.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/led-class-multicolor.h> +#include <linux/leds.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/property.h> +#include <linux/reset.h> +#include <linux/spinlock.h> + +#define LEDC_CTRL_REG 0x0000 +#define LEDC_CTRL_REG_DATA_LENGTH GENMASK(28, 16) +#define LEDC_CTRL_REG_RGB_MODE GENMASK(8, 6) +#define LEDC_CTRL_REG_LEDC_EN BIT(0) +#define LEDC_T01_TIMING_CTRL_REG 0x0004 +#define LEDC_T01_TIMING_CTRL_REG_T1H GENMASK(26, 21) +#define LEDC_T01_TIMING_CTRL_REG_T1L GENMASK(20, 16) +#define LEDC_T01_TIMING_CTRL_REG_T0H GENMASK(10, 6) +#define LEDC_T01_TIMING_CTRL_REG_T0L GENMASK(5, 0) +#define LEDC_RESET_TIMING_CTRL_REG 0x000c +#define LEDC_RESET_TIMING_CTRL_REG_TR GENMASK(28, 16) +#define LEDC_RESET_TIMING_CTRL_REG_LED_NUM GENMASK(9, 0) +#define LEDC_DATA_REG 0x0014 +#define LEDC_DMA_CTRL_REG 0x0018 +#define LEDC_DMA_CTRL_REG_DMA_EN BIT(5) +#define LEDC_DMA_CTRL_REG_FIFO_TRIG_LEVEL GENMASK(4, 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_WLW GENMASK(15, 10) +#define LEDC_INT_STS_REG_FIFO_CPUREQ_INT BIT(1) +#define LEDC_INT_STS_REG_TRANS_FINISH_INT BIT(0) + +#define LEDC_FIFO_DEPTH 32U +#define LEDC_MAX_LEDS 1024 +#define LEDC_CHANNELS_PER_LED 3 /* RGB */ + +#define LEDS_TO_BYTES(n) ((n) * sizeof(u32)) + +struct sun50i_a100_ledc_led { + struct led_classdev_mc mc_cdev; + struct mc_subled subled_info[LEDC_CHANNELS_PER_LED]; + u32 addr; +}; + +#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; + unsigned int pio_length; + unsigned int pio_offset; + + spinlock_t lock; + unsigned int next_length; + bool xfer_active; + + u32 format; + struct sun50i_a100_ledc_timing timing; + + u32 max_addr; + u32 num_leds; + struct sun50i_a100_ledc_led leds[] __counted_by(num_leds); +}; + +static int sun50i_a100_ledc_dma_xfer(struct sun50i_a100_ledc *priv, unsigned 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, unsigned int fifo_used) +{ + unsigned int burst, length, offset; + u32 control; + + length = priv->pio_length; + offset = priv->pio_offset; + burst = min(length, LEDC_FIFO_DEPTH - fifo_used); + + 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) { + control = readl(priv->base + LEDC_INT_CTRL_REG); + control |= LEDC_INT_CTRL_REG_FIFO_CPUREQ_INT_EN; + writel(control, priv->base + LEDC_INT_CTRL_REG); + } + } else { + /* Disable the request IRQ once all data is written. */ + control = readl(priv->base + LEDC_INT_CTRL_REG); + control &= ~LEDC_INT_CTRL_REG_FIFO_CPUREQ_INT_EN; + writel(control, priv->base + LEDC_INT_CTRL_REG); + } +} + +static void sun50i_a100_ledc_start_xfer(struct sun50i_a100_ledc *priv, unsigned int length) +{ + bool use_dma = false; + u32 control; + + if (priv->dma_chan && length > LEDC_FIFO_DEPTH) { + int ret; + + ret = sun50i_a100_ledc_dma_xfer(priv, length); + if (ret) + dev_warn(priv->dev, "Failed to set up DMA (%d), using PIO\n", ret); + else + use_dma = true; + } + + /* The DMA trigger level must be at least the burst length. */ + control = FIELD_PREP(LEDC_DMA_CTRL_REG_DMA_EN, use_dma) | + FIELD_PREP_CONST(LEDC_DMA_CTRL_REG_FIFO_TRIG_LEVEL, LEDC_FIFO_DEPTH / 2); + writel(control, priv->base + LEDC_DMA_CTRL_REG); + + control = readl(priv->base + LEDC_CTRL_REG); + control &= ~LEDC_CTRL_REG_DATA_LENGTH; + control |= FIELD_PREP(LEDC_CTRL_REG_DATA_LENGTH, length) | LEDC_CTRL_REG_LEDC_EN; + writel(control, priv->base + LEDC_CTRL_REG); + + if (!use_dma) { + /* The FIFO is empty when starting a new transfer. */ + unsigned int fifo_used = 0; + + priv->pio_length = length; + priv->pio_offset = 0; + + sun50i_a100_ledc_pio_xfer(priv, fifo_used); + } +} + +static irqreturn_t sun50i_a100_ledc_irq(int irq, void *data) +{ + struct sun50i_a100_ledc *priv = data; + u32 status; + + status = readl(priv->base + LEDC_INT_STS_REG); + + if (status & LEDC_INT_STS_REG_TRANS_FINISH_INT) { + unsigned int next_length; + + spin_lock(&priv->lock); + + /* If another transfer is queued, dequeue and start it. */ + 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 (status & LEDC_INT_STS_REG_FIFO_CPUREQ_INT) { + /* Continue the current transfer. */ + sun50i_a100_ledc_pio_xfer(priv, FIELD_GET(LEDC_INT_STS_REG_FIFO_WLW, status)); + } + + /* Clear the W1C status bits. */ + writel(status, 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); + unsigned int next_length; + unsigned long flags; + bool xfer_active; + + led_mc_calc_color_components(mc_cdev, brightness); + + priv->buffer[led->addr] = led->subled_info[0].brightness << 16 | + led->subled_info[1].brightness << 8 | + led->subled_info[2].brightness; + + spin_lock_irqsave(&priv->lock, flags); + + /* Start, enqueue, or extend an enqueued transfer, as appropriate. */ + next_length = max(priv->next_length, led->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(struct device *dev, + struct sun50i_a100_ledc *priv) +{ + const char *format = "grb"; + u32 i; + + device_property_read_string(dev, "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; + } + } + + return dev_err_probe(dev, -EINVAL, "Bad pixel format '%s'\n", format); +} + +static void sun50i_a100_ledc_set_format(struct sun50i_a100_ledc *priv) +{ + u32 control; + + control = readl(priv->base + LEDC_CTRL_REG); + control &= ~LEDC_CTRL_REG_RGB_MODE; + control |= FIELD_PREP(LEDC_CTRL_REG_RGB_MODE, priv->format); + writel(control, 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(struct device *dev, + struct sun50i_a100_ledc *priv) +{ + struct sun50i_a100_ledc_timing *timing = &priv->timing; + + *timing = sun50i_a100_ledc_default_timing; + + device_property_read_u32(dev, "allwinner,t0h-ns", &timing->t0h_ns); + device_property_read_u32(dev, "allwinner,t0l-ns", &timing->t0l_ns); + device_property_read_u32(dev, "allwinner,t1h-ns", &timing->t1h_ns); + device_property_read_u32(dev, "allwinner,t1l-ns", &timing->t1l_ns); + device_property_read_u32(dev, "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; + u32 control; + + if (!mod_freq) + return; + + cycle_ns = NSEC_PER_SEC / mod_freq; + control = FIELD_PREP(LEDC_T01_TIMING_CTRL_REG_T1H, timing->t1h_ns / cycle_ns) | + FIELD_PREP(LEDC_T01_TIMING_CTRL_REG_T1L, timing->t1l_ns / cycle_ns) | + FIELD_PREP(LEDC_T01_TIMING_CTRL_REG_T0H, timing->t0h_ns / cycle_ns) | + FIELD_PREP(LEDC_T01_TIMING_CTRL_REG_T0L, timing->t0l_ns / cycle_ns); + writel(control, priv->base + LEDC_T01_TIMING_CTRL_REG); + + control = FIELD_PREP(LEDC_RESET_TIMING_CTRL_REG_TR, timing->treset_ns / cycle_ns) | + FIELD_PREP(LEDC_RESET_TIMING_CTRL_REG_LED_NUM, priv->max_addr); + writel(control, 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); + 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); + + writel(LEDC_INT_CTRL_REG_GLOBAL_INT_EN | LEDC_INT_CTRL_REG_TRANS_FINISH_INT_EN, + 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); + + /* Wait for all transfers to complete. */ + for (;;) { + unsigned long flags; + bool xfer_active; + + spin_lock_irqsave(&priv->lock, flags); + xfer_active = priv->xfer_active; + spin_unlock_irqrestore(&priv->lock, flags); + if (!xfer_active) + break; + + msleep(1); + } + + 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; + + dma_release_channel(priv->dma_chan); +} + +static int sun50i_a100_ledc_probe(struct platform_device *pdev) +{ + struct dma_slave_config dma_cfg = {}; + struct led_init_data init_data = {}; + struct sun50i_a100_ledc_led *led; + struct device *dev = &pdev->dev; + struct sun50i_a100_ledc *priv; + struct fwnode_handle *child; + struct resource *mem; + u32 max_addr = 0; + u32 num_leds = 0; + int irq, ret; + + /* + * The maximum LED address must be known in sun50i_a100_ledc_resume() before + * class device registration, so parse and validate the subnodes up front. + */ + device_for_each_child_node(dev, child) { + u32 addr, color; + + ret = fwnode_property_read_u32(child, "reg", &addr); + if (ret || addr >= LEDC_MAX_LEDS) { + fwnode_handle_put(child); + return dev_err_probe(dev, -EINVAL, "'reg' must be between 0 and %d\n", + LEDC_MAX_LEDS - 1); + } + + ret = fwnode_property_read_u32(child, "color", &color); + if (ret || color != LED_COLOR_ID_RGB) { + fwnode_handle_put(child); + return dev_err_probe(dev, -EINVAL, "'color' must be LED_COLOR_ID_RGB\n"); + } + + max_addr = max(max_addr, addr); + num_leds++; + } + + if (!num_leds) + return -ENODEV; + + priv = devm_kzalloc(dev, struct_size(priv, leds, num_leds), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + priv->max_addr = max_addr; + priv->num_leds = num_leds; + spin_lock_init(&priv->lock); + dev_set_drvdata(dev, priv); + + ret = sun50i_a100_ledc_parse_format(dev, priv); + if (ret) + return ret; + + ret = sun50i_a100_ledc_parse_timing(dev, 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)) { + if (PTR_ERR(priv->dma_chan) != -ENODEV) + return PTR_ERR(priv->dma_chan); + + priv->dma_chan = NULL; + + priv->buffer = devm_kzalloc(dev, LEDS_TO_BYTES(LEDC_MAX_LEDS), GFP_KERNEL); + if (!priv->buffer) + return -ENOMEM; + } else { + 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 = dmam_alloc_attrs(dmaengine_get_dma_device(priv->dma_chan), + LEDS_TO_BYTES(LEDC_MAX_LEDS), &priv->dma_handle, + GFP_KERNEL, DMA_ATTR_WRITE_COMBINE); + 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; + + led = priv->leds; + device_for_each_child_node(dev, child) { + struct led_classdev *cdev; + + /* The node was already validated above. */ + fwnode_property_read_u32(child, "reg", &led->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 = child; + + ret = led_classdev_multicolor_register_ext(dev, &led->mc_cdev, &init_data); + if (ret) { + dev_err_probe(dev, ret, "Failed to register multicolor LED %u", led->addr); + goto err_put_child; + } + + led++; + } + + dev_info(dev, "Registered %u LEDs\n", num_leds); + + return 0; + +err_put_child: + fwnode_handle_put(child); + while (led-- > priv->leds) + led_classdev_multicolor_unregister(&led->mc_cdev); + sun50i_a100_ledc_suspend(&pdev->dev); + + return ret; +} + +static void sun50i_a100_ledc_remove(struct platform_device *pdev) +{ + struct sun50i_a100_ledc *priv = platform_get_drvdata(pdev); + + for (u32 i = 0; i < priv->num_leds; i++) + led_classdev_multicolor_unregister(&priv->leds[i].mc_cdev); + 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 DEFINE_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_new = sun50i_a100_ledc_remove, + .shutdown = sun50i_a100_ledc_remove, + .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 <samuel@sholland.org>"); +MODULE_DESCRIPTION("Allwinner A100 LED controller driver"); +MODULE_LICENSE("GPL"); |