[PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[Chen-Yu Tsai]

Some SoCs do not support clk delays for MMC in the clock control unit.
These include the old controllers in A10/A10s/A13/R8, and the new eMMC
controller in A64. The config structure for these controllers do not
specify clk_delays, but the check for this was replaced in commit
b0600daebf31 ("mmc: sunxi: Support controllers that can use both old
and new timings").

This patch adds back the check for clk_delays, and also adds comments
for both checks in sunxi_mmc_clk_set_phase().

Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use
		      both old and new timings")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
---
This fixes an mmc regression on A10/A10s/A13/R8 and A64 introduced
by the A83T mmc patches.

v1 was inlined in a reply to "mmc: sunxi: fix new timings mode on A64
EMMC (MMC2) controller"

Changes since v1:

  - Polished comments 

I've tested this on my A10 Cubieboard and A20 Cubieboard2.
---
 drivers/mmc/host/sunxi-mmc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
index 3777517982dd..9dc6d726ec49 100644
--- a/drivers/mmc/host/sunxi-mmc.c
+++ b/drivers/mmc/host/sunxi-mmc.c
@@ -722,9 +722,14 @@ static int sunxi_mmc_clk_set_phase(struct sunxi_mmc_host *host,
 {
 	int index;
 
+	/* clk controller delays not used under new timings mode */
 	if (host->use_new_timings)
 		return 0;
 
+	/* some old controllers don't support delays */
+	if (!host->cfg->clk_delays)
+		return 0;
+
 	/* determine delays */
 	if (rate <= 400000) {
 		index = SDXC_CLK_400K;
-- 
2.13.3

[PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[icenowy at aosc.io]

? 2017-08-08 15:02?Chen-Yu Tsai ???
> Some SoCs do not support clk delays for MMC in the clock control unit.
> These include the old controllers in A10/A10s/A13/R8, and the new eMMC
> controller in A64. The config structure for these controllers do not
> specify clk_delays, but the check for this was replaced in commit
> b0600daebf31 ("mmc: sunxi: Support controllers that can use both old
> and new timings").
> 
> This patch adds back the check for clk_delays, and also adds comments
> for both checks in sunxi_mmc_clk_set_phase().
> 
> Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use
> 		      both old and new timings")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Should I add a Tested-by here?

> ---
> This fixes an mmc regression on A10/A10s/A13/R8 and A64 introduced
> by the A83T mmc patches.
> 
> v1 was inlined in a reply to "mmc: sunxi: fix new timings mode on A64
> EMMC (MMC2) controller"
> 
> Changes since v1:
> 
>   - Polished comments
> 
> I've tested this on my A10 Cubieboard and A20 Cubieboard2.
> ---
>  drivers/mmc/host/sunxi-mmc.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/mmc/host/sunxi-mmc.c 
> b/drivers/mmc/host/sunxi-mmc.c
> index 3777517982dd..9dc6d726ec49 100644
> --- a/drivers/mmc/host/sunxi-mmc.c
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -722,9 +722,14 @@ static int sunxi_mmc_clk_set_phase(struct
> sunxi_mmc_host *host,
>  {
>  	int index;
> 
> +	/* clk controller delays not used under new timings mode */
>  	if (host->use_new_timings)
>  		return 0;
> 
> +	/* some old controllers don't support delays */
> +	if (!host->cfg->clk_delays)
> +		return 0;
> +
>  	/* determine delays */
>  	if (rate <= 400000) {
>  		index = SDXC_CLK_400K;

[linux-sunxi] Re: [PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[Chen-Yu Tsai]

On Tue, Aug 8, 2017 at 3:07 PM,  <icenowy@aosc.io> wrote:
> ? 2017-08-08 15:02?Chen-Yu Tsai ???
>>
>> Some SoCs do not support clk delays for MMC in the clock control unit.
>> These include the old controllers in A10/A10s/A13/R8, and the new eMMC
>> controller in A64. The config structure for these controllers do not
>> specify clk_delays, but the check for this was replaced in commit
>> b0600daebf31 ("mmc: sunxi: Support controllers that can use both old
>> and new timings").
>>
>> This patch adds back the check for clk_delays, and also adds comments
>> for both checks in sunxi_mmc_clk_set_phase().
>>
>> Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use
>>                       both old and new timings")
>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>
>
> Should I add a Tested-by here?

If you tested it, then yes. :)

ChenYu

[linux-sunxi] Re: [PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[icenowy at aosc.io]

? 2017-08-08 15:10?Chen-Yu Tsai ???
> On Tue, Aug 8, 2017 at 3:07 PM,  <icenowy@aosc.io> wrote:
>> ? 2017-08-08 15:02?Chen-Yu Tsai ???
>>> 
>>> Some SoCs do not support clk delays for MMC in the clock control 
>>> unit.
>>> These include the old controllers in A10/A10s/A13/R8, and the new 
>>> eMMC
>>> controller in A64. The config structure for these controllers do not
>>> specify clk_delays, but the check for this was replaced in commit
>>> b0600daebf31 ("mmc: sunxi: Support controllers that can use both old
>>> and new timings").
>>> 
>>> This patch adds back the check for clk_delays, and also adds comments
>>> for both checks in sunxi_mmc_clk_set_phase().
>>> 
>>> Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use
>>>                       both old and new timings")
>>> Signed-off-by: Chen-Yu Tsai <wens@csie.org>
>> 
>> 
>> Should I add a Tested-by here?
> 
> If you tested it, then yes. :)

I tested it on A64 MMC2.

So:

Tested-by: Icenowy Zheng <icenowy@aosc.io>

> 
> ChenYu

[PATCH v2] mmc: sunxi: Fix NULL pointer reference on clk_delays

[Ulf Hansson]

On 8 August 2017 at 09:02, Chen-Yu Tsai <wens@csie.org> wrote:
> Some SoCs do not support clk delays for MMC in the clock control unit.
> These include the old controllers in A10/A10s/A13/R8, and the new eMMC
> controller in A64. The config structure for these controllers do not
> specify clk_delays, but the check for this was replaced in commit
> b0600daebf31 ("mmc: sunxi: Support controllers that can use both old
> and new timings").
>
> This patch adds back the check for clk_delays, and also adds comments
> for both checks in sunxi_mmc_clk_set_phase().
>
> Fixes: b0600daebf31 ("mmc: sunxi: Support controllers that can use
>                       both old and new timings")
> Signed-off-by: Chen-Yu Tsai <wens@csie.org>

Thanks, applied for next!

Kind regards
Uffe

> ---
> This fixes an mmc regression on A10/A10s/A13/R8 and A64 introduced
> by the A83T mmc patches.
>
> v1 was inlined in a reply to "mmc: sunxi: fix new timings mode on A64
> EMMC (MMC2) controller"
>
> Changes since v1:
>
>   - Polished comments
>
> I've tested this on my A10 Cubieboard and A20 Cubieboard2.
> ---
>  drivers/mmc/host/sunxi-mmc.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> index 3777517982dd..9dc6d726ec49 100644
> --- a/drivers/mmc/host/sunxi-mmc.c
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -722,9 +722,14 @@ static int sunxi_mmc_clk_set_phase(struct sunxi_mmc_host *host,
>  {
>         int index;
>
> +       /* clk controller delays not used under new timings mode */
>         if (host->use_new_timings)
>                 return 0;
>
> +       /* some old controllers don't support delays */
> +       if (!host->cfg->clk_delays)
> +               return 0;
> +
>         /* determine delays */
>         if (rate <= 400000) {
>                 index = SDXC_CLK_400K;
> --
> 2.13.3
>