[PATCH RFC 1/2] libahci_platform: add ahci_platform_get_of_property
From: mark.rutland@arm.com (Mark Rutland)
Date: 2014-06-18 14:03:52
Also in:
linux-devicetree, linux-ide
On Wed, Jun 18, 2014 at 05:54:08AM +0100, Zhangfei Gao wrote:
Instead of setting hflags in different files, ahci_platform_get_of_property set hpriv->flags when ahci_platform_init_host according to property in dts.
The AHCI_HFLAGS are a Linux implementation detail, so it would be nice to have a good justification for each of these being turned into DT properties.
quoted hunk ↗ jump to hunk
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org> --- .../devicetree/bindings/ata/ahci-platform.txt | 9 +++++ drivers/ata/libahci_platform.c | 39 ++++++++++++++++++++ 2 files changed, 48 insertions(+)diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt index c96d8dcf98fd..c0b9f6e76ba4 100644 --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt@@ -26,6 +26,15 @@ Optional properties: - clocks : must contain the sata, sata_ref and ahb clocks - clock-names : must contain "ahb" for the ahb clock +- no-ncq: when present, controller can't do NCQ, turning off CAP_NCQ +- 32bit-only: when present, controller can't do 64bit DMA, forcing 32bit +- no-msi: when present, no PCI MSI +- no-pmp: when present, controller can't do PMP, turning off CAP_PMP +- yes-ncq: when present,controller can do NCQ, turning on CAP_NCQ +- no-suspend: when present, controller can't do suspend +- yes-fbs: when present, controller can do FBS, turning on CAP_FBS +- no-fbs: when present, controller can't do FBS, turning off CAP_FBS
There is absolutely no reason to mention CAP_* here; the DT should describe the HW, not Linux internals. Do these all make sense to be placed in DT? I worry that for other quirks we may need more flags in future. For that reason I'd rather figure this out in the driver based on the compatible string.
quoted hunk ↗ jump to hunk
+ Examples: sata at ffe08000 { compatible = "snps,spear-ahci";diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c index 3a5b4ed25a4f..880b9f360056 100644 --- a/drivers/ata/libahci_platform.c +++ b/drivers/ata/libahci_platform.c@@ -278,6 +278,44 @@ err_out: } EXPORT_SYMBOL_GPL(ahci_platform_get_resources); +#ifdef CONFIG_OF +static void ahci_platform_get_of_property(struct platform_device *pdev, + struct ahci_host_priv *hpriv) +{ + struct device_node *np = pdev->dev.of_node; + + if (of_device_is_available(np)) { + if (of_get_property(np, "no-ncq", NULL)) + hpriv->flags |= AHCI_HFLAG_NO_NCQ;
For boolean flags please use of_property_read_bool. Mark.