[PATCH 4/4] clk: stm32: Fix ltdc's clock turn off by clk_disable_unused() after kernel startup

[Patrice CHOTARD]

Hi Dillon

On 5/14/21 1:02 PM, dillon.minfei at gmail.com wrote:
> From: Dillon Min <dillon.minfei at gmail.com>
> 
> stm32's clk driver register two ltdc gate clk to clk core by
> clk_hw_register_gate() and clk_hw_register_composite()
> 
> first: 'stm32f429_gates[]', clk name is 'ltdc', which no user to use.
> second: 'stm32f429_aux_clk[]', clk name is 'lcd-tft', used by ltdc driver
> 
> both of them point to the same offset of stm32's RCC register. after
> kernel enter console, clk core turn off ltdc's clk as 'stm32f429_gates[]'
> is no one to use. but, actually 'stm32f429_aux_clk[]' is in use.
> 
> Fixes: daf2d117cbca ("clk: stm32f4: Add lcd-tft clock")
> Signed-off-by: Dillon Min <dillon.minfei at gmail.com>
> Acked-by: Stephen Boyd <sboyd at kernel.org>
> Link: https://lore.kernel.org/linux-arm-kernel/1590564453-24499-7-git-send-email-dillon.minfei@gmail.com/
> ---
>  drivers/clk/clk-stm32f4.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/drivers/clk/clk-stm32f4.c b/drivers/clk/clk-stm32f4.c
> index 42ca2dd86aea..f4156a8a6041 100644
> --- a/drivers/clk/clk-stm32f4.c
> +++ b/drivers/clk/clk-stm32f4.c
> @@ -129,7 +129,6 @@ static const struct stm32f4_gate_data stm32f429_gates[] __initconst = {
>  	{ STM32F4_RCC_APB2ENR, 20,	"spi5",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 21,	"spi6",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 22,	"sai1",		"apb2_div" },
> -	{ STM32F4_RCC_APB2ENR, 26,	"ltdc",		"apb2_div" },
>  };
>  
>  static const struct stm32f4_gate_data stm32f469_gates[] __initconst = {
> @@ -211,7 +210,6 @@ static const struct stm32f4_gate_data stm32f469_gates[] __initconst = {
>  	{ STM32F4_RCC_APB2ENR, 20,	"spi5",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 21,	"spi6",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 22,	"sai1",		"apb2_div" },
> -	{ STM32F4_RCC_APB2ENR, 26,	"ltdc",		"apb2_div" },
>  };
>  
>  static const struct stm32f4_gate_data stm32f746_gates[] __initconst = {
> @@ -286,7 +284,6 @@ static const struct stm32f4_gate_data stm32f746_gates[] __initconst = {
>  	{ STM32F4_RCC_APB2ENR, 21,	"spi6",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 22,	"sai1",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 23,	"sai2",		"apb2_div" },
> -	{ STM32F4_RCC_APB2ENR, 26,	"ltdc",		"apb2_div" },
>  };
>  
>  static const struct stm32f4_gate_data stm32f769_gates[] __initconst = {
> @@ -364,7 +361,6 @@ static const struct stm32f4_gate_data stm32f769_gates[] __initconst = {
>  	{ STM32F4_RCC_APB2ENR, 21,	"spi6",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 22,	"sai1",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 23,	"sai2",		"apb2_div" },
> -	{ STM32F4_RCC_APB2ENR, 26,	"ltdc",		"apb2_div" },
>  	{ STM32F4_RCC_APB2ENR, 30,	"mdio",		"apb2_div" },
>  };
>  
> 

Reviewed-by: Patrice Chotard <patrice.chotard at foss.st.com>

Thanks
Patrice