Date:   Thu, 16 Mar 2023 13:34:22 +0000
From:   Lee Jones <lee@kernel.org>
To:     Samuel Holland <samuel@sholland.org>
Cc:     Pavel Machek <pavel@ucw.cz>, linux-leds@vger.kernel.org,
        Chen-Yu Tsai <wens@csie.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        Conor Dooley <conor@kernel.org>, Guo Ren <guoren@kernel.org>,
        Heiko Stuebner <heiko.stuebner@vrull.eu>,
        Heiko Stuebner <heiko@sntech.de>,
        Jisheng Zhang <jszhang@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Rob Herring <robh+dt@kernel.org>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-riscv@lists.infradead.org, linux-sunxi@lists.linux.dev
Subject: Re: [RESEND PATCH v7 2/5] leds: sun50i-a100: New driver for the A100
 LED controller
Message-ID: <20230316133422.GM9667@google.com>
References: <20221231235541.13568-1-samuel@sholland.org>
 <20221231235541.13568-3-samuel@sholland.org>
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In-Reply-To: <20221231235541.13568-3-samuel@sholland.org>
Precedence: bulk

On Sat, 31 Dec 2022, Samuel Holland wrote:

> 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.
>
> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
> Signed-off-by: Samuel Holland <samuel@sholland.org>
> ---
>
> Changes in v7:
>  - Use DEFINE_SIMPLE_DEV_PM_OPS
>
> Changes in v5:
>  - Rename the driver R329 -> A100, since that is the actual original
>    implementation
>
> Changes in v4:
>  - Depend on LEDS_CLASS_MULTICOLOR
>
> Changes in v3:
>  - 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
>
> Changes in v2:
>  - Renamed from sunxi-ledc to sun50i-r329-ledc
>  - Added missing "static" to functions/globals as reported by 0day bot
>
>  drivers/leds/Kconfig            |   9 +
>  drivers/leds/Makefile           |   1 +
>  drivers/leds/leds-sun50i-a100.c | 555 ++++++++++++++++++++++++++++++++
>  3 files changed, 565 insertions(+)
>  create mode 100644 drivers/leds/leds-sun50i-a100.c

Nice driver.  Just some nits below.

> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
> index 499d0f215a8b..4f4c515ed7d7 100644
> --- a/drivers/leds/Kconfig
> +++ b/drivers/leds/Kconfig
> @@ -281,6 +281,15 @@ 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.

Did you run spellcheck on this?

>  config LEDS_SUNFIRE
>  	tristate "LED support for SunFire servers."
>  	depends on LEDS_CLASS
> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
> index 4fd2f92cd198..a6ee3f5cf7be 100644
> --- 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
> diff --git a/drivers/leds/leds-sun50i-a100.c b/drivers/leds/leds-sun50i-a100.c
> new file mode 100644
> index 000000000000..30fa9be2cf2d
> --- /dev/null
> +++ b/drivers/leds/leds-sun50i-a100.c
> @@ -0,0 +1,555 @@
> +// SPDX-License-Identifier: GPL-2.0
> +//
> +// Copyright (c) 2021-2022 Samuel Holland <samuel@sholland.org>

Please update.

> +// Partly based on drivers/leds/leds-turris-omnia.c, which is:
> +//     Copyright (c) 2020 by Marek Behún <kabel@kernel.org>
> +//

What is this line commenting?

Could you please re-do this header to use C-style comments please.

> +#include <linux/clk.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/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm.h>
> +#include <linux/reset.h>
> +#include <linux/spinlock.h>
> +
> +#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 {

Is this information likely to change on a per-LED basis?

> +	struct led_classdev_mc mc_cdev;
> +	struct mc_subled subled_info[3];

What is 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);

Didn't we already establish that length was 0?

> +	}
> +
> +	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);

How useful is this, really?

Could you consider removing it?

> +	val = readl(priv->base + LEDC_CTRL_REG);
> +	val &= ~LEDC_CTRL_REG_DATA_LENGTH;
> +	val |= length << 16 | LEDC_CTRL_REG_LEDC_EN;

Why 16?  Please consider defining all magic numbers.

  BLAH_BLAH_SHIFT ?

> +	writel(val, priv->base + LEDC_CTRL_REG);
> +
> +	if (length > LEDC_FIFO_DEPTH) {
> +		int ret = sun50i_a100_ledc_dma_xfer(priv, length);

Looks odd.  It's way more common to separate the call from the declaration.

> +		if (!ret)
> +			return;
> +
> +		dev_warn(priv->dev, "Failed to set up DMA: %d\n", ret);

This looks like an error.

Please tell the user we're falling back to PIO.

> +	}
> +
> +	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;

This is clearly not a def_id.  'data' looks like a common alternative.

> +	u32 val;
> +
> +	val = readl(priv->base + LEDC_INT_STS_REG);

'val' is a terrible variable name.  'status'?

> +	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);

Did 'val' change?  If this is intentional, perhaps a comment to clarify.

> +	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;

Not really an address is it?  'offset' or something better?

> +	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]);

As above.

> +	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);

Cramped code is not easy to read.  Please consider some '\n's.

> +	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) {

Does the pre-increment hold any significance?

If not, please use the more common implementation of post-incrementing.

> +		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;

'timing'

> +	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;

'control'

> +	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);

What happens if this is NULL or an error?

> +	if (priv->buffer)
> +		dma_free_wc(dma_dev, LEDS_TO_BYTES(priv->num_leds),
> +			    priv->buffer, priv->dma_handle);

'\n'

> +	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;

'\n'

> +	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;

'\n'

> +	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",

Doesn't sounds like an address.

> +				priv->num_leds - 1);

100-chars - no need to wrap.

Please apply this everywhere.

> +			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");

Then why even provide the option?

> +			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",

"multicolor LED"

> +				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;

return sun50i_a100_ledc_suspend(&pdev->dev);

> +}
> +
> +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 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		= 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 <samuel@sholland.org>");
> +MODULE_DESCRIPTION("Allwinner A100 LED controller driver");
> +MODULE_LICENSE("GPL");
> --
> 2.37.4
>

--
Lee Jones [李琼斯]