Re: [PATCH v2 10/10] Input: ams_delta_serio: Get FIQ buffer from platform_data

From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>,
	Aaro Koskinen <aaro.koskinen@iki.fi>,
	"David S . Miller " <davem@davemloft.net>,
	Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Randy Dunlap <rdunlap@infradead.org>,
	Linus Walleij <linus.walleij@linaro.org>,
	Mark Brown <broonie@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
	linux-input@vger.kernel.org, linux-gpio@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 10/10] Input: ams_delta_serio: Get FIQ buffer from platform_data
Date: Thu, 21 Jun 2018 17:11:46 -0700	[thread overview]
Message-ID: <20180622001146.GG79890@dtor-ws> (raw)
In-Reply-To: <20180621224128.17623-10-jmkrzyszt@gmail.com>

On Fri, Jun 22, 2018 at 12:41:28AM +0200, Janusz Krzysztofik wrote:
> Instead of exporting the FIQ buffer symbol to be used in
> ams-delta-serio driver, pass it to the driver as platform_data.
> 
> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>

Input bits look good.

Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

> ---
> Changelog:
> v2: rebased on v4.18-rc1, no conflicts
> 
>  arch/arm/mach-omap1/ams-delta-fiq.c         |  6 +++---
>  arch/arm/mach-omap1/board-ams-delta.c       |  8 ++++++++
>  drivers/input/serio/ams_delta_serio.c       | 20 +++++++++++++-------
>  include/linux/platform_data/ams-delta-fiq.h |  4 ----
>  4 files changed, 24 insertions(+), 14 deletions(-)
> 
> diff --git a/arch/arm/mach-omap1/ams-delta-fiq.c b/arch/arm/mach-omap1/ams-delta-fiq.c
> index 82ca4246a5e4..b0dc7ddf5877 100644
> --- a/arch/arm/mach-omap1/ams-delta-fiq.c
> +++ b/arch/arm/mach-omap1/ams-delta-fiq.c
> @@ -40,8 +40,7 @@ static struct fiq_handler fh = {
>   * keystrokes received from the qwerty keyboard.  See
>   * <linux/platform_data/ams-delta-fiq.h> for details of offsets.
>   */
> -unsigned int fiq_buffer[1024];
> -EXPORT_SYMBOL(fiq_buffer);
> +static unsigned int fiq_buffer[1024];
>  
>  static struct irq_chip *irq_chip;
>  static struct irq_data *irq_data[16];
> @@ -203,9 +202,10 @@ void __init ams_delta_init_fiq(struct gpio_chip *chip,
>  	val = omap_readl(OMAP_IH1_BASE + offset) | 1;
>  	omap_writel(val, OMAP_IH1_BASE + offset);
>  
> -	/* Initialize serio device IRQ resource */
> +	/* Initialize serio device IRQ resource and platform_data */
>  	serio->resource[0].start = gpiod_to_irq(clk);
>  	serio->resource[0].end = serio->resource[0].start;
> +	serio->dev.platform_data = fiq_buffer;
>  
>  	/*
>  	 * Since FIQ handler performs handling of GPIO registers for
> diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c
> index 84177ba3e39a..772892487827 100644
> --- a/arch/arm/mach-omap1/board-ams-delta.c
> +++ b/arch/arm/mach-omap1/board-ams-delta.c
> @@ -520,6 +520,14 @@ static struct resource ams_delta_serio_resources[] = {
>  static struct platform_device ams_delta_serio_device = {
>  	.name		= "ams-delta-serio",
>  	.id		= PLATFORM_DEVID_NONE,
> +	.dev		= {
> +		/*
> +		 * Initialize .platform_data explicitly with NULL to
> +		 * indicate it is going to be used.  It will be replaced
> +		 * with FIQ buffer address as soon as FIQ is initialized.
> +		 */
> +		.platform_data = NULL,
> +	},
>  	.num_resources	= ARRAY_SIZE(ams_delta_serio_resources),
>  	.resource	= ams_delta_serio_resources,
>  };
> diff --git a/drivers/input/serio/ams_delta_serio.c b/drivers/input/serio/ams_delta_serio.c
> index c1f8226f172e..f8663d7891f2 100644
> --- a/drivers/input/serio/ams_delta_serio.c
> +++ b/drivers/input/serio/ams_delta_serio.c
> @@ -37,6 +37,7 @@ MODULE_LICENSE("GPL");
>  struct ams_delta_serio {
>  	struct serio *serio;
>  	struct regulator *vcc;
> +	unsigned int *fiq_buffer;
>  };
>  
>  static int check_data(struct serio *serio, int data)
> @@ -66,22 +67,23 @@ static int check_data(struct serio *serio, int data)
>  static irqreturn_t ams_delta_serio_interrupt(int irq, void *dev_id)
>  {
>  	struct ams_delta_serio *priv = dev_id;
> -	int *circ_buff = &fiq_buffer[FIQ_CIRC_BUFF];
> +	int *circ_buff = &priv->fiq_buffer[FIQ_CIRC_BUFF];
>  	int data, dfl;
>  	u8 scancode;
>  
> -	fiq_buffer[FIQ_IRQ_PEND] = 0;
> +	priv->fiq_buffer[FIQ_IRQ_PEND] = 0;
>  
>  	/*
>  	 * Read data from the circular buffer, check it
>  	 * and then pass it on the serio
>  	 */
> -	while (fiq_buffer[FIQ_KEYS_CNT] > 0) {
> +	while (priv->fiq_buffer[FIQ_KEYS_CNT] > 0) {
>  
> -		data = circ_buff[fiq_buffer[FIQ_HEAD_OFFSET]++];
> -		fiq_buffer[FIQ_KEYS_CNT]--;
> -		if (fiq_buffer[FIQ_HEAD_OFFSET] == fiq_buffer[FIQ_BUF_LEN])
> -			fiq_buffer[FIQ_HEAD_OFFSET] = 0;
> +		data = circ_buff[priv->fiq_buffer[FIQ_HEAD_OFFSET]++];
> +		priv->fiq_buffer[FIQ_KEYS_CNT]--;
> +		if (priv->fiq_buffer[FIQ_HEAD_OFFSET] ==
> +		    priv->fiq_buffer[FIQ_BUF_LEN])
> +			priv->fiq_buffer[FIQ_HEAD_OFFSET] = 0;
>  
>  		dfl = check_data(priv->serio, data);
>  		scancode = (u8) (data >> 1) & 0xFF;
> @@ -116,6 +118,10 @@ static int ams_delta_serio_init(struct platform_device *pdev)
>  	if (!priv)
>  		return -ENOMEM;
>  
> +	priv->fiq_buffer = pdev->dev.platform_data;
> +	if (!priv->fiq_buffer)
> +		return -EINVAL;
> +
>  	priv->vcc = devm_regulator_get(&pdev->dev, "vcc");
>  	if (IS_ERR(priv->vcc)) {
>  		err = PTR_ERR(priv->vcc);
> diff --git a/include/linux/platform_data/ams-delta-fiq.h b/include/linux/platform_data/ams-delta-fiq.h
> index dc0f835ea918..cf4589ccb720 100644
> --- a/include/linux/platform_data/ams-delta-fiq.h
> +++ b/include/linux/platform_data/ams-delta-fiq.h
> @@ -55,8 +55,4 @@
>  
>  #define FIQ_CIRC_BUFF		30      /*Start of circular buffer */
>  
> -#ifndef __ASSEMBLER__
> -extern unsigned int fiq_buffer[];
> -#endif
> -
>  #endif
> -- 
> 2.16.4
> 

-- 
Dmitry