Messages in this thread | | | Date | Wed, 9 Apr 2014 08:59:21 -0700 | Subject | Re: [rfc]pwm: add BCM2835 PWM driver | From | Tim Kryger <> |
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On Tue, Apr 8, 2014 at 6:27 PM, Stephen Warren <swarren@wwwdotorg.org> wrote: > On 04/08/2014 05:02 PM, Tim Kryger wrote: >> On Thu, Apr 3, 2014 at 6:44 AM, Bart Tanghe <bart.tanghe@thomasmore.be> wrote: >>> need some recommendation >>> the memory mapped io registers of the bcm2835 pwm hardware are spreaded >>> over the memory mapped io >>> gpio config 0x20200004 - clk config 0x201010A0 - pwm configuration 0x2020C000 >>> to handle this, I've used the base address of the memory mapped io >>> so I can use positive offsets >> >> So the registers for this PWM are located in three distinct memory regions? > ... >>> +struct bcm2835_pwm_chip { >>> + struct pwm_chip chip; >>> + struct device *dev; >>> + int channel; >>> + void __iomem *mmio; >> >> One pointer isn't going to be enough. You need three. >> >> I suggest renaming the first and adding two more: >> >> void __iomem *base_pwm; >> void __iomem *base_clk; >> void __iomem *base_alt; > > Sorry, I forgot about this patch. One comment here; the PWM driver can't > touch the clock or alt registers; those should be owned by the clock > driver, and the driver for whatever alt is (pinmux - don't recall what > it's touching there).
Absolutely. If these registers are owned by other drivers, go through them.
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