Messages in this thread | | | Date | Wed, 17 Jun 2015 16:39:01 +0200 | From | Boris Brezillon <> | Subject | Re: [PATCH v2 2/2] clk: at91: modify PMC peripheral clock to deal with newer register layout |
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On Wed, 17 Jun 2015 14:40:39 +0200 Nicolas Ferre <nicolas.ferre@atmel.com> 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. > > Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> --- > v2: - modify header file beforehand so that we can use consistent field naming > > > drivers/clk/at91/clk-peripheral.c | 20 ++++++++++++++------ > 1 file changed, 14 insertions(+), 6 deletions(-) > > diff --git a/drivers/clk/at91/clk-peripheral.c b/drivers/clk/at91/clk-peripheral.c > index 61d0adda7088..1e7dcc57925a 100644 > --- a/drivers/clk/at91/clk-peripheral.c > +++ b/drivers/clk/at91/clk-peripheral.c > @@ -161,14 +161,18 @@ 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_MASK) | > - 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_MASK)); > + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_DIV_MASK; > + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_DIV(periph->div) > + | AT91_PMC_PCR_CMD > + | AT91_PMC_PCR_EN); > + pmc_unlock(pmc); > return 0; > } > > @@ -176,12 +180,16 @@ 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_MASK) | > - AT91_PMC_PCR_CMD); > + pmc_lock(pmc); > + pmc_write(pmc, AT91_PMC_PCR, (periph->id & AT91_PMC_PCR_PID_MASK)); > + tmp = pmc_read(pmc, AT91_PMC_PCR) & ~AT91_PMC_PCR_EN; > + pmc_write(pmc, AT91_PMC_PCR, tmp | AT91_PMC_PCR_CMD); > + pmc_unlock(pmc); > } > > static int clk_sam9x5_peripheral_is_enabled(struct clk_hw *hw)
-- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com
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