Hi Nicolas, On Wed, 10 Jun 2015 15:42:44 +0200 Nicolas Ferre <[email protected]> wrote:
> As some more information is added to the PCR register, we'd better use > a copy of its content and modify just the peripheral-related bits. > Implement a read-modify-write for the enable() and disable() callbacks. > > Header file is also modified to have the PCR_DIV mask. > > Signed-off-by: Nicolas Ferre <[email protected]> Apart from the below comment you can add my: Acked-by: Boris Brezillon <[email protected]> > --- > drivers/clk/at91/clk-peripheral.c | 19 +++++++++++++------ > include/linux/clk/at91_pmc.h | 3 ++- > 2 files changed, 15 insertions(+), 7 deletions(-) > > diff --git a/drivers/clk/at91/clk-peripheral.c > b/drivers/clk/at91/clk-peripheral.c > index 597fed423d7d..37e2fea14890 100644 > --- a/drivers/clk/at91/clk-peripheral.c > +++ b/drivers/clk/at91/clk-peripheral.c > @@ -161,14 +161,17 @@ static int clk_sam9x5_peripheral_enable(struct clk_hw > *hw) > { > struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); > struct at91_pmc *pmc = periph->pmc; > + u32 tmp; > > if (periph->id < PERIPHERAL_ID_MIN) > return 0; > > - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID) | > - AT91_PMC_PCR_CMD | > - AT91_PMC_PCR_DIV(periph->div) | > - AT91_PMC_PCR_EN); > + pmc_lock(pmc); > + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID)); > + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_P_DIV; > + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_PDIV(periph->div) > + | AT91_PMC_PCR_EN); > + pmc_unlock(pmc); > return 0; > } > > @@ -176,12 +179,16 @@ static void clk_sam9x5_peripheral_disable(struct clk_hw > *hw) > { > struct clk_sam9x5_peripheral *periph = to_clk_sam9x5_peripheral(hw); > struct at91_pmc *pmc = periph->pmc; > + u32 tmp; > > if (periph->id < PERIPHERAL_ID_MIN) > return; > > - pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID) | > - AT91_PMC_PCR_CMD); > + pmc_lock(pmc); > + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID)); > + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_EN; > + pmc_write(pmc, AT91_PMC_PCR, tmp); > + pmc_unlock(pmc); > } > > static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw) > diff --git a/include/linux/clk/at91_pmc.h b/include/linux/clk/at91_pmc.h > index 7669f7618f39..4685c3d62f94 100644 > --- a/include/linux/clk/at91_pmc.h > +++ b/include/linux/clk/at91_pmc.h > @@ -184,7 +184,8 @@ extern void __iomem *at91_pmc_base; > #define AT91_PMC_PCR 0x10c /* Peripheral Control > Register [some SAM9 and SAMA5] */ > #define AT91_PMC_PCR_PID (0x3f << 0) /* > Peripheral ID */ > #define AT91_PMC_PCR_CMD (0x1 << 12) /* > Command (read=0, write=1) */ > -#define AT91_PMC_PCR_DIV(n) ((n) << 16) /* > Divisor Value */ > +#define AT91_PMC_PCR_P_DIV (0x3 << 16) /* > Divisor mask */ How about renaming this macro into AT91_PMC_PCR_PDIV_MSK ? I know the macro names in this file are not consistent, but maybe it's time to choose appropriate names for new AT91_PMC macros. Best Regards, Boris -- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
