Re: [PATCH 2/2] leds: simatic-ipc-leds: Don't directly deref ioremap_resource() returned ptr

[Hans de Goede <hdegoede@redhat.com>]

Hi Henning,

On 1/28/22 10:30, Henning Schild wrote:
> Hi Hans,
> 
> this looks fine but also looks like someone should test it. What is the
> timeline on that? I would want that tested but will need a few more
> days to actually sit next to boxes and look at LEDs.

It would be nice to get this fix in before say 5.17-rc5, so testing
this a couple of days from now is fine.

Talking about merging this...

Pavel, since the original patch has landed through the pdx86 tree
in 5.17-rc1 and since these 2 patches are LED patches I was sorta
expecting you to pick these up.  But if it is easier for you,
I would also happy to make these patches part of a pdx86 fixes
pull-req for 5.17 .

Regards,

Hans






> 
> Gerd maybe you can try that? Should affect 127E only and can probably
> be applied onto our out-of-tree repo.
> 
> regards,
> Henning
> 
> Am Mon, 17 Jan 2022 12:21:09 +0100
> schrieb Hans de Goede <hdegoede@redhat.com>:
> 
>> Sparse (rightly) currently gives the following warning:
>>
>> drivers/leds/simple/simatic-ipc-leds.c:155:40:
>>  sparse: sparse: incorrect type in assignment (different address
>> spaces) expected void *static [toplevel] simatic_ipc_led_memory
>>  got void [noderef] __iomem *
>>
>> Fix this by changing the type of simatic_ipc_led_memory to void
>> __iomem * and use readl()/writel() to access it.
>>
>> Cc: Henning Schild <henning.schild@siemens.com>
>> Reported-by: kernel test robot <lkp@intel.com>
>> Signed-off-by: Hans de Goede <hdegoede@redhat.com>
>> ---
>> Note this is not tested on actual hw, since I do not have the hw in
>> question ---
>>  drivers/leds/simple/simatic-ipc-leds.c | 32
>> +++++++++++++++----------- 1 file changed, 18 insertions(+), 14
>> deletions(-)
>>
>> diff --git a/drivers/leds/simple/simatic-ipc-leds.c
>> b/drivers/leds/simple/simatic-ipc-leds.c index
>> 179110448659..078d43f5ba38 100644 ---
>> a/drivers/leds/simple/simatic-ipc-leds.c +++
>> b/drivers/leds/simple/simatic-ipc-leds.c @@ -41,7 +41,7 @@ static
>> struct simatic_ipc_led simatic_ipc_leds_io[] = { /* the actual start
>> will be discovered with PCI, 0 is a placeholder */ static struct
>> resource simatic_ipc_led_mem_res = DEFINE_RES_MEM_NAMED(0, SZ_4K,
>> KBUILD_MODNAME); -static void *simatic_ipc_led_memory;
>> +static void __iomem *simatic_ipc_led_memory;
>>  
>>  static struct simatic_ipc_led simatic_ipc_leds_mem[] = {
>>  	{0x500 + 0x1A0, "red:" LED_FUNCTION_STATUS "-1"},
>> @@ -92,21 +92,22 @@ static void simatic_ipc_led_set_mem(struct
>> led_classdev *led_cd, enum led_brightness brightness)
>>  {
>>  	struct simatic_ipc_led *led = cdev_to_led(led_cd);
>> +	void __iomem *reg = simatic_ipc_led_memory + led->value;
>> +	u32 val;
>>  
>> -	u32 *p;
>> -
>> -	p = simatic_ipc_led_memory + led->value;
>> -	*p = (*p & ~1) | (brightness == LED_OFF);
>> +	val = readl(reg);
>> +	val = (val & ~1) | (brightness == LED_OFF);
>> +	writel(val, reg);
>>  }
>>  
>>  static enum led_brightness simatic_ipc_led_get_mem(struct
>> led_classdev *led_cd) {
>>  	struct simatic_ipc_led *led = cdev_to_led(led_cd);
>> +	void __iomem *reg = simatic_ipc_led_memory + led->value;
>> +	u32 val;
>>  
>> -	u32 *p;
>> -
>> -	p = simatic_ipc_led_memory + led->value;
>> -	return (*p & 1) ? LED_OFF : led_cd->max_brightness;
>> +	val = readl(reg);
>> +	return (val & 1) ? LED_OFF : led_cd->max_brightness;
>>  }
>>  
>>  static int simatic_ipc_leds_probe(struct platform_device *pdev)
>> @@ -116,8 +117,9 @@ static int simatic_ipc_leds_probe(struct
>> platform_device *pdev) struct simatic_ipc_led *ipcled;
>>  	struct led_classdev *cdev;
>>  	struct resource *res;
>> +	void __iomem *reg;
>>  	int err, type;
>> -	u32 *p;
>> +	u32 val;
>>  
>>  	switch (plat->devmode) {
>>  	case SIMATIC_IPC_DEVICE_227D:
>> @@ -157,11 +159,13 @@ static int simatic_ipc_leds_probe(struct
>> platform_device *pdev) return PTR_ERR(simatic_ipc_led_memory);
>>  
>>  		/* initialize power/watchdog LED */
>> -		p = simatic_ipc_led_memory + 0x500 + 0x1D8; /*
>> PM_WDT_OUT */
>> -		*p = (*p & ~1);
>> -		p = simatic_ipc_led_memory + 0x500 + 0x1C0; /*
>> PM_BIOS_BOOT_N */
>> -		*p = (*p | 1);
>> +		reg = simatic_ipc_led_memory + 0x500 + 0x1D8; /*
>> PM_WDT_OUT */
>> +		val = readl(reg);
>> +		writel(val & ~1, reg);
>>  
>> +		reg = simatic_ipc_led_memory + 0x500 + 0x1C0; /*
>> PM_BIOS_BOOT_N */
>> +		val = readl(reg);
>> +		writel(val | 1, reg);
>>  		break;
>>  	default:
>>  		return -ENODEV;
>