[PATCH v7 05/15] ahci-platform: "Library-ise" ahci_probe functionality
Bartlomiej Zolnierkiewicz
b.zolnierkie at samsung.com
Mon Mar 3 13:38:46 EST 2014
Hi,
On Saturday, February 22, 2014 04:53:34 PM Hans de Goede wrote:
> ahci_probe consists of 3 steps:
> 1) Get resources (get mmio, clks, regulator)
> 2) Enable resources, handled by ahci_platform_enable_resouces
> 3) The more or less standard ahci-host controller init sequence
>
> This commit refactors step 1 and 3 into separate functions, so the platform
> drivers for AHCI implementations which need a specific order in step 2,
> and / or need to do some custom register poking at some time, can re-use
> ahci-platform.c code without needing to copy and paste it.
>
> Note that ahci_platform_init_host's prototype takes the 3 non function
> members of ahci_platform_data as arguments, the idea is that drivers using
> the new exported utility functions will not use ahci_platform_data at all,
> and hopefully in the future ahci_platform_data can go away entirely.
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
> drivers/ata/ahci_platform.c | 195 ++++++++++++++++++++++++++++--------------
> include/linux/ahci_platform.h | 14 +++
> 2 files changed, 144 insertions(+), 65 deletions(-)
>
> diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
> index 6ebbc17..7f3f2ac 100644
> --- a/drivers/ata/ahci_platform.c
> +++ b/drivers/ata/ahci_platform.c
> @@ -201,64 +201,64 @@ void ahci_platform_disable_resources(struct ahci_host_priv *hpriv)
> }
> EXPORT_SYMBOL_GPL(ahci_platform_disable_resources);
>
> -static void ahci_put_clks(struct ahci_host_priv *hpriv)
> +static void ahci_platform_put_resources(struct device *dev, void *res)
> {
> + struct ahci_host_priv *hpriv = res;
> int c;
>
> for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
> clk_put(hpriv->clks[c]);
> }
>
> -static int ahci_probe(struct platform_device *pdev)
> +/**
> + * ahci_platform_get_resources - Get platform resources
> + * @pdev: platform device to get resources for
> + *
> + * This function allocates an ahci_host_priv struct, and gets the
> + * following resources, storing a reference to them inside the returned
> + * struct:
> + *
> + * 1) mmio registers (IORESOURCE_MEM 0, mandatory)
> + * 2) regulator for controlling the targets power (optional)
> + * 3) 0 - AHCI_MAX_CLKS clocks, as specified in the devs devicetree node,
> + * or for non devicetree enabled platforms a single clock
> + *
> + * LOCKING:
> + * None.
> + *
> + * RETURNS:
> + * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
> + */
> +struct ahci_host_priv *ahci_platform_get_resources(
> + struct platform_device *pdev)
It would be better if these two lines were merged:
struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev)
> {
> struct device *dev = &pdev->dev;
> - struct ahci_platform_data *pdata = dev_get_platdata(dev);
> - const struct platform_device_id *id = platform_get_device_id(pdev);
> - struct ata_port_info pi = ahci_port_info[id ? id->driver_data : 0];
> - const struct ata_port_info *ppi[] = { &pi, NULL };
> struct ahci_host_priv *hpriv;
> - struct ata_host *host;
> - struct resource *mem;
> struct clk *clk;
> - int irq;
> - int n_ports;
> - int i;
> - int rc;
> + int i, rc = -ENOMEM;
>
> - mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> - if (!mem) {
> - dev_err(dev, "no mmio space\n");
> - return -EINVAL;
> - }
> + if (!devres_open_group(dev, NULL, GFP_KERNEL))
> + return ERR_PTR(-ENOMEM);
>
> - irq = platform_get_irq(pdev, 0);
> - if (irq <= 0) {
> - dev_err(dev, "no irq\n");
> - return -EINVAL;
> - }
> + hpriv = devres_alloc(ahci_platform_put_resources, sizeof(*hpriv),
> + GFP_KERNEL);
> + if (!hpriv)
> + goto err_out;
>
> - if (pdata && pdata->ata_port_info)
> - pi = *pdata->ata_port_info;
> + devres_add(dev, hpriv);
>
> - hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
> - if (!hpriv) {
> - dev_err(dev, "can't alloc ahci_host_priv\n");
> - return -ENOMEM;
> - }
> -
> - hpriv->flags |= (unsigned long)pi.private_data;
> -
> - hpriv->mmio = devm_ioremap(dev, mem->start, resource_size(mem));
> + hpriv->mmio = devm_ioremap_resource(dev,
> + platform_get_resource(pdev, IORESOURCE_MEM, 0));
> if (!hpriv->mmio) {
This should use IS_ERR() as devm_ioremap_resource() returns a pointer
to the remapped memory or an ERR_PTR() encoded error code on failure.
> - dev_err(dev, "can't map %pR\n", mem);
> - return -ENOMEM;
> + dev_err(dev, "no mmio space\n");
Not needed, devm_ioremap_resource() prints an error message on error.
> + goto err_out;
This should set rc to an error value from devm_ioremap_resource()
instead of returning -ENOMEM.
> }
>
> hpriv->target_pwr = devm_regulator_get_optional(dev, "target");
> if (IS_ERR(hpriv->target_pwr)) {
> rc = PTR_ERR(hpriv->target_pwr);
> if (rc == -EPROBE_DEFER)
> - return -EPROBE_DEFER;
> + goto err_out;
> hpriv->target_pwr = NULL;
> }
>
> @@ -277,33 +277,62 @@ static int ahci_probe(struct platform_device *pdev)
> if (IS_ERR(clk)) {
> rc = PTR_ERR(clk);
> if (rc == -EPROBE_DEFER)
> - goto free_clk;
> + goto err_out;
> break;
> }
> hpriv->clks[i] = clk;
> }
>
> - rc = ahci_platform_enable_resources(hpriv);
> - if (rc)
> - goto free_clk;
> + devres_remove_group(dev, NULL);
> + return hpriv;
>
> - /*
> - * Some platforms might need to prepare for mmio region access,
> - * which could be done in the following init call. So, the mmio
> - * region shouldn't be accessed before init (if provided) has
> - * returned successfully.
> - */
> - if (pdata && pdata->init) {
> - rc = pdata->init(dev, hpriv->mmio);
> - if (rc)
> - goto disable_resources;
> - }
> +err_out:
> + devres_release_group(dev, NULL);
> + return ERR_PTR(rc);
> +}
> +EXPORT_SYMBOL_GPL(ahci_platform_get_resources);
[...]
The rest of the patch looks OK.
Best regards,
--
Bartlomiej Zolnierkiewicz
Samsung R&D Institute Poland
Samsung Electronics
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