| Message ID | 20210107164825.21919-1-rf@opensource.cirrus.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | spi: bcm2835: Set controller max_speed_hz | expand |
On Thu, Jan 07, 2021 at 04:48:25PM +0000, Richard Fitzgerald wrote: > If the controller max_speed_hz is not set, the spi core will limit all > transfers to 0 Hz so only the minimum possible bus frequency would be used. That was a bug and is now fixed.
On Thu, 7 Jan 2021 16:48:25 +0000, Richard Fitzgerald wrote: > Set the struct spi_controller max_speed_hz. This is based on the > reported source clock frequency during probe. The maximum bus clock > is half the source clock (as per the code in bcm2835_spi_transfer_one). > > If the controller max_speed_hz is not set, the spi core will limit all > transfers to 0 Hz so only the minimum possible bus frequency would be used. Applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next Thanks! [1/1] spi: bcm2835: Set controller max_speed_hz commit: c6892892a95debac8050579b0709214b7b28b514 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 197485f2c2b2..8e161f4f7766 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -1307,6 +1307,8 @@ static int bcm2835_spi_probe(struct platform_device *pdev) return dev_err_probe(&pdev->dev, PTR_ERR(bs->clk), "could not get clk\n"); + ctlr->max_speed_hz = clk_get_rate(bs->clk) / 2; + bs->irq = platform_get_irq(pdev, 0); if (bs->irq <= 0) return bs->irq ? bs->irq : -ENODEV;
Set the struct spi_controller max_speed_hz. This is based on the reported source clock frequency during probe. The maximum bus clock is half the source clock (as per the code in bcm2835_spi_transfer_one). If the controller max_speed_hz is not set, the spi core will limit all transfers to 0 Hz so only the minimum possible bus frequency would be used. Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com> --- drivers/spi/spi-bcm2835.c | 2 ++ 1 file changed, 2 insertions(+)