linux-kernel - Re: [PATCH 08/13] mfd: sec: store hardware revision in sec_pmic

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Message-ID: <982158427bae79e15c92ad0198b398258e262ef6.camel@linaro.org>
Date: Fri, 14 Nov 2025 13:14:19 +0000
From: André Draszik <andre.draszik@...aro.org>
To: Kaustabh Chakraborty <kauschluss@...root.org>, Lee Jones
 <lee@...nel.org>,  Pavel Machek <pavel@...nel.org>, Rob Herring
 <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>,  Conor Dooley
 <conor+dt@...nel.org>, MyungJoo Ham <myungjoo.ham@...sung.com>, Chanwoo
 Choi	 <cw00.choi@...sung.com>, Sebastian Reichel <sre@...nel.org>,
 Krzysztof Kozlowski <krzk@...nel.org>, Alexandre Belloni
 <alexandre.belloni@...tlin.com>, Jonathan Corbet	 <corbet@....net>
Cc: linux-leds@...r.kernel.org, devicetree@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org, 
	linux-samsung-soc@...r.kernel.org, linux-rtc@...r.kernel.org, 
	linux-doc@...r.kernel.org
Subject: Re: [PATCH 08/13] mfd: sec: store hardware revision in sec_pmic_dev
 and add S2MU005 support

On Fri, 2025-11-14 at 00:35 +0530, Kaustabh Chakraborty wrote:
> The device revision matters in cases when in some PMICs, the correct
> register offsets very in different revisions. Instead of just debug
> printing the value, store it in the driver data struct.
> 
> Unlike other devices, S2MU005 has its hardware revision ID in register
> offset 0x73. Allow handling different devices and add support for S2MU005.
> 
> Signed-off-by: Kaustabh Chakraborty <kauschluss@...root.org>
> ---
>  drivers/mfd/sec-common.c         | 30 ++++++++++++++++++++++++------
>  include/linux/mfd/samsung/core.h |  3 +++
>  2 files changed, 27 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/mfd/sec-common.c b/drivers/mfd/sec-common.c
> index 4c5f4dc2905b..f51c53e7a164 100644
> --- a/drivers/mfd/sec-common.c
> +++ b/drivers/mfd/sec-common.c
> @@ -16,6 +16,7 @@
>  #include <linux/mfd/samsung/irq.h>
>  #include <linux/mfd/samsung/s2mps11.h>
>  #include <linux/mfd/samsung/s2mps13.h>
> +#include <linux/mfd/samsung/s2mu005.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/pm.h>
> @@ -86,17 +87,34 @@ static const struct mfd_cell s2mu005_devs[] = {
>  	MFD_CELL_OF("s2mu005-rgb", NULL, NULL, 0, 0, "samsung,s2mu005-rgb"),
>  };
>  
> -static void sec_pmic_dump_rev(struct sec_pmic_dev *sec_pmic)
> +static void sec_pmic_store_rev(struct sec_pmic_dev *sec_pmic)
>  {
> -	unsigned int val;
> +	unsigned int reg, mask, shift;
>  
>  	/* For s2mpg1x, the revision is in a different regmap */
>  	if (sec_pmic->device_type == S2MPG10)
>  		return;
>  
> -	/* For each device type, the REG_ID is always the first register */
> -	if (!regmap_read(sec_pmic->regmap_pmic, S2MPS11_REG_ID, &val))
> -		dev_dbg(sec_pmic->dev, "Revision: 0x%x\n", val);
> +	switch (sec_pmic->device_type) {
> +	case S2MU005:
> +		reg = S2MU005_REG_ID;
> +		mask = S2MU005_ID_MASK;
> +		shift = S2MU005_ID_SHIFT;
> +		break;
> +	default:
> +		/* For other device types, the REG_ID is always the first register. */
> +		reg = S2MPS11_REG_ID;
> +		mask = ~0;
> +		shift = 0;
> +	}
> +
> +	if (!regmap_read(sec_pmic->regmap_pmic, reg, &sec_pmic->revision))
> +		return;

You should probably propagate the error up to the caller here.

Cheers,
Andre'

> +
> +	sec_pmic->revision &= mask;
> +	sec_pmic->revision >>= shift;
> +
> +	dev_dbg(sec_pmic->dev, "Revision: 0x%x\n", sec_pmic->revision);
>  }
>  
>  static void sec_pmic_configure(struct sec_pmic_dev *sec_pmic)
> @@ -236,7 +254,7 @@ int sec_pmic_probe(struct device *dev, int device_type, unsigned int irq,
>  		return ret;
>  
>  	sec_pmic_configure(sec_pmic);
> -	sec_pmic_dump_rev(sec_pmic);
> +	sec_pmic_store_rev(sec_pmic);
>  
>  	return ret;
>  }
> diff --git a/include/linux/mfd/samsung/core.h b/include/linux/mfd/samsung/core.h
> index fc07f7944dcd..ccd1bfa15b85 100644
> --- a/include/linux/mfd/samsung/core.h
> +++ b/include/linux/mfd/samsung/core.h
> @@ -63,6 +63,7 @@ enum sec_device_type {
>   * @irq_base:		Base IRQ number for device, required for IRQs
>   * @irq:		Generic IRQ number for device
>   * @irq_data:		Runtime data structure for IRQ controller
> + * @revision:		Revision number of the device
>   * @wakeup:		Whether or not this is a wakeup device
>   */
>  struct sec_pmic_dev {
> @@ -74,6 +75,8 @@ struct sec_pmic_dev {
>  	int device_type;
>  	int irq;
>  	struct regmap_irq_chip_data *irq_data[MAX_IRQ_CHIPS];
> +
> +	unsigned int revision;
>  };
>  
>  struct sec_platform_data {