Re: [PATCH v2 1/2] ata: ahci_platform: Manage SATA PHY

From: Bartlomiej Zolnierkiewicz
Date: Thu Oct 17 2013 - 09:57:24 EST



Hi,

On Wednesday, October 16, 2013 02:42:52 PM Roger Quadros wrote:
> From: Balaji T K <balajitk@xxxxxx>
>
> Some platforms have a PHY hooked up to the
> SATA controller. The PHY needs to be initialized
> and powered up for SATA to work. We do that
> using the PHY framework.
>
> [Roger Q] Cleaned up.
>
> CC: Tejun Heo <tj@xxxxxxxxxx>
> Signed-off-by: Balaji T K <balajitk@xxxxxx>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
> .../devicetree/bindings/ata/ahci-platform.txt | 3 +-
> drivers/ata/ahci.h | 2 ++
> drivers/ata/ahci_platform.c | 29 +++++++++++++++++++-
> 3 files changed, 32 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
> index 89de156..c8a6cea 100644
> --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
> +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
> @@ -4,7 +4,8 @@ SATA nodes are defined to describe on-chip Serial ATA controllers.
> Each SATA controller should have its own node.
>
> Required properties:
> -- compatible : compatible list, contains "snps,spear-ahci"
> +- compatible : compatible list, contains "snps,spear-ahci",
> + snps,exynos5440-ahci or "snps,dwc-ahci"

minor nit:
s/snps,exynos5440-ahci/"snps,exynos5440-ahci"/

> - interrupts : <interrupt mapping for SATA IRQ>
> - reg : <registers mapping>
>
> diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
> index 1145637..94484cb 100644
> --- a/drivers/ata/ahci.h
> +++ b/drivers/ata/ahci.h
> @@ -37,6 +37,7 @@
>
> #include <linux/clk.h>
> #include <linux/libata.h>
> +#include <linux/phy/phy.h>
>
> /* Enclosure Management Control */
> #define EM_CTRL_MSG_TYPE 0x000f0000
> @@ -322,6 +323,7 @@ struct ahci_host_priv {
> u32 em_buf_sz; /* EM buffer size in byte */
> u32 em_msg_type; /* EM message type */
> struct clk *clk; /* Only for platforms supporting clk */
> + struct phy *phy; /* If platforms use phy */

minor nit:
s/If platforms use phy/If platform uses PHY/

> void *plat_data; /* Other platform data */
> };
>
> diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
> index 2daaee0..5a0f1418 100644
> --- a/drivers/ata/ahci_platform.c
> +++ b/drivers/ata/ahci_platform.c
> @@ -141,6 +141,21 @@ static int ahci_probe(struct platform_device *pdev)
> }
> }
>
> + hpriv->phy = devm_phy_get(dev, "sata-phy");
> + if (IS_ERR(hpriv->phy)) {
> + dev_dbg(dev, "can't get sata-phy\n");
> + /* return only if -EPROBE_DEFER */
> + if (PTR_ERR(hpriv->phy) == -EPROBE_DEFER) {
> + rc = -EPROBE_DEFER;
> + goto disable_unprepare_clk;
> + }
> + }
> +
> + if (!IS_ERR(hpriv->phy)) {
> + phy_init(hpriv->phy);
> + phy_power_on(hpriv->phy);
> + }
> +
> /*
> * Some platforms might need to prepare for mmio region access,
> * which could be done in the following init call. So, the mmio
> @@ -150,7 +165,7 @@ static int ahci_probe(struct platform_device *pdev)
> if (pdata && pdata->init) {
> rc = pdata->init(dev, hpriv->mmio);
> if (rc)
> - goto disable_unprepare_clk;
> + goto disable_phy;
> }
>
> ahci_save_initial_config(dev, hpriv,
> @@ -220,6 +235,12 @@ static int ahci_probe(struct platform_device *pdev)
> pdata_exit:
> if (pdata && pdata->exit)
> pdata->exit(dev);
> +disable_phy:
> + if (!IS_ERR(hpriv->phy)) {
> + phy_power_off(hpriv->phy);
> + phy_exit(hpriv->phy);
> + }
> +
> disable_unprepare_clk:
> if (!IS_ERR(hpriv->clk))
> clk_disable_unprepare(hpriv->clk);
> @@ -238,6 +259,11 @@ static void ahci_host_stop(struct ata_host *host)
> if (pdata && pdata->exit)
> pdata->exit(dev);
>
> + if (!IS_ERR(hpriv->phy)) {
> + phy_power_off(hpriv->phy);
> + phy_exit(hpriv->phy);
> + }
> +
> if (!IS_ERR(hpriv->clk)) {
> clk_disable_unprepare(hpriv->clk);
> clk_put(hpriv->clk);
> @@ -328,6 +354,7 @@ static SIMPLE_DEV_PM_OPS(ahci_pm_ops, ahci_suspend, ahci_resume);

Shouldn't phy_power_off/on also be used in ahci_suspend() and ahci_resume()?

> static const struct of_device_id ahci_of_match[] = {
> { .compatible = "snps,spear-ahci", },
> { .compatible = "snps,exynos5440-ahci", },
> + { .compatible = "snps,dwc-ahci", },

This change together with ahci-platform.txt one should be in a separate patch.

> {},
> };
> MODULE_DEVICE_TABLE(of, ahci_of_match);

Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics

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