On Wed, Jun 21, 2017 at 10:57:30AM +0200, Linus Walleij wrote:
> This fixes a regression on the FTPCI100 PCI driver.
>
> When the clock controller was augmented to probe clocks
> from the platform device except to the most basic clocks
> pertaining to timers, clocks may return an error pointer
> containing -EPROBE_DEFER.
>
> This hit the PCI driver which would try to continue
> without the clocks, but the actual clocks appeared later,
> so we did not pick them up properly, and in the end of
> the boot, these clocks get gated off if no users register,
> so the PCI host became numbed off and silently nonworking.
>
> The clocks for this PCI bus are defined properly for all
> platforms implementing it, so we should make them compulsory
> before new users arrive so we have our resources under
> control.
>
> This makes the driver bail out of probe with any error
> code from the clock, including -EPROBE_DEFER so that we
> again have a clean boot.
>
> Fixes: cea186ac1e45 ("pci: ftpci100: Add clock handling")
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
I folded this into the "pci: ftpci100: Add clock handling" commit,
thanks!
> ---
> ChangeLog v1->v2:
> - Inadvertedly managed to switch PTR_ERR() for ERR_PTR()
> in the code, and the compile screamed.
> ---
> drivers/pci/host/pci-ftpci100.c | 28 ++++++++++++----------------
> 1 file changed, 12 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/pci/host/pci-ftpci100.c b/drivers/pci/host/pci-ftpci100.c
> index d3bf153a2ab2..db31ab21884e 100644
> --- a/drivers/pci/host/pci-ftpci100.c
> +++ b/drivers/pci/host/pci-ftpci100.c
> @@ -463,24 +463,20 @@ static int faraday_pci_probe(struct platform_device *pdev)
>
> /* Retrieve and enable optional clocks */
> clk = devm_clk_get(dev, "PCLK");
> - if (IS_ERR(clk)) {
> - dev_err(dev, "no PCLK available\n");
> - } else {
> - ret = clk_prepare_enable(clk);
> - if (ret) {
> - dev_err(dev, "could not prepare PCLK\n");
> - return ret;
> - }
> + if (IS_ERR(clk))
> + return PTR_ERR(clk);
> + ret = clk_prepare_enable(clk);
> + if (ret) {
> + dev_err(dev, "could not prepare PCLK\n");
> + return ret;
> }
> p->bus_clk = devm_clk_get(dev, "PCICLK");
> - if (IS_ERR(p->bus_clk)) {
> - dev_err(dev, "no PCICLK available\n");
> - } else {
> - ret = clk_prepare_enable(p->bus_clk);
> - if (ret) {
> - dev_err(dev, "could not prepare PCICLK\n");
> - return ret;
> - }
> + if (IS_ERR(p->bus_clk))
> + return PTR_ERR(clk);
> + ret = clk_prepare_enable(p->bus_clk);
> + if (ret) {
> + dev_err(dev, "could not prepare PCICLK\n");
> + return ret;
> }
>
> regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> --
> 2.9.4
>
