[PATCH v6 07/18] ahci-platform: "Library-ise" ahci_probe functionality

[Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

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-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 drivers/ata/ahci_platform.c   | 158 ++++++++++++++++++++++++------------------
 include/linux/ahci_platform.h |  14 ++++
 2 files changed, 106 insertions(+), 66 deletions(-)

diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 1cce7a2..b260ebe 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -150,60 +150,31 @@ 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)
-{
-	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)
+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 i, irq, max_clk, n_ports, rc;
-
-	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!mem) {
-		dev_err(dev, "no mmio space\n");
-		return -EINVAL;
-	}
-
-	irq = platform_get_irq(pdev, 0);
-	if (irq <= 0) {
-		dev_err(dev, "no irq\n");
-		return -EINVAL;
-	}
-
-	if (pdata && pdata->ata_port_info)
-		pi = *pdata->ata_port_info;
+	int i, max_clk, rc;
 
 	hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
 	if (!hpriv) {
 		dev_err(dev, "can't alloc ahci_host_priv\n");
-		return -ENOMEM;
+		return ERR_PTR(-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) {
-		dev_err(dev, "can't map %pR\n", mem);
-		return -ENOMEM;
+		dev_err(dev, "no mmio space\n");
+		return ERR_PTR(-EINVAL);
 	}
 
 	hpriv->target_pwr = devm_regulator_get_optional(dev, "target");
 	if (IS_ERR(hpriv->target_pwr)) {
 		if (PTR_ERR(hpriv->target_pwr) == -EPROBE_DEFER)
-			return -EPROBE_DEFER;
+			return ERR_PTR(-EPROBE_DEFER);
 		hpriv->target_pwr = NULL;
 	}
 
@@ -223,27 +194,48 @@ static int ahci_probe(struct platform_device *pdev)
 		hpriv->clks[i] = clk;
 	}
 
-	rc = ahci_platform_enable_resources(hpriv);
-	if (rc)
-		goto free_clk;
+	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);
-		if (rc)
-			goto disable_resources;
-	}
+free_clk:
+	while (--i >= 0)
+		clk_put(hpriv->clks[i]);
+	return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_GPL(ahci_platform_get_resources);
+
+void ahci_platform_put_resources(struct ahci_host_priv *hpriv)
+{
+	int c;
+
+	for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
+		clk_put(hpriv->clks[c]);
+}
+EXPORT_SYMBOL_GPL(ahci_platform_put_resources);
+
+
+int ahci_platform_init_host(struct platform_device *pdev,
+			    struct ahci_host_priv *hpriv,
+			    const struct ata_port_info *pi_template,
+			    unsigned int force_port_map,
+			    unsigned int mask_port_map)
+{
+	struct device *dev = &pdev->dev;
+	struct ata_port_info pi = *pi_template;
+	const struct ata_port_info *ppi[] = { &pi, NULL };
+	struct ata_host *host;
+	int i, irq, n_ports, rc;
 
-	ahci_save_initial_config(dev, hpriv,
-		pdata ? pdata->force_port_map : 0,
-		pdata ? pdata->mask_port_map  : 0);
+	irq = platform_get_irq(pdev, 0);
+	if (irq <= 0) {
+		dev_err(dev, "no irq\n");
+		return -EINVAL;
+	}
 
 	/* prepare host */
+	hpriv->flags |= (unsigned long)pi.private_data;
+
+	ahci_save_initial_config(dev, hpriv, force_port_map, mask_port_map);
+
 	if (hpriv->cap & HOST_CAP_NCQ)
 		pi.flags |= ATA_FLAG_NCQ;
 
@@ -260,10 +252,8 @@ static int ahci_probe(struct platform_device *pdev)
 	n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));
 
 	host = ata_host_alloc_pinfo(dev, ppi, n_ports);
-	if (!host) {
-		rc = -ENOMEM;
-		goto pdata_exit;
-	}
+	if (!host)
+		return -ENOMEM;
 
 	host->private_data = hpriv;
 
@@ -278,7 +268,8 @@ static int ahci_probe(struct platform_device *pdev)
 	for (i = 0; i < host->n_ports; i++) {
 		struct ata_port *ap = host->ports[i];
 
-		ata_port_desc(ap, "mmio %pR", mem);
+		ata_port_desc(ap, "mmio %pR",
+			      platform_get_resource(pdev, IORESOURCE_MEM, 0));
 		ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);
 
 		/* set enclosure management message type */
@@ -292,13 +283,48 @@ static int ahci_probe(struct platform_device *pdev)
 
 	rc = ahci_reset_controller(host);
 	if (rc)
-		goto pdata_exit;
+		return rc;
 
 	ahci_init_controller(host);
 	ahci_print_info(host, "platform");
 
-	rc = ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
-			       &ahci_platform_sht);
+	return ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
+				 &ahci_platform_sht);
+}
+EXPORT_SYMBOL_GPL(ahci_platform_init_host);
+
+static int ahci_probe(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 ahci_host_priv *hpriv;
+	int rc;
+
+	hpriv = ahci_platform_get_resources(pdev);
+	if (IS_ERR(hpriv))
+		return PTR_ERR(hpriv);
+
+	rc = ahci_platform_enable_resources(hpriv);
+	if (rc)
+		goto put_resources;
+
+	/*
+	 * 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);
+		if (rc)
+			goto disable_resources;
+	}
+
+	rc = ahci_platform_init_host(pdev, hpriv,
+				     &ahci_port_info[id ? id->driver_data : 0],
+				     pdata ? pdata->force_port_map : 0,
+				     pdata ? pdata->mask_port_map  : 0);
 	if (rc)
 		goto pdata_exit;
 
@@ -308,8 +334,8 @@ pdata_exit:
 		pdata->exit(dev);
 disable_resources:
 	ahci_platform_disable_resources(hpriv);
-free_clk:
-	ahci_put_clks(hpriv);
+put_resources:
+	ahci_platform_put_resources(hpriv);
 	return rc;
 }
 
@@ -323,7 +349,7 @@ static void ahci_host_stop(struct ata_host *host)
 		pdata->exit(dev);
 
 	ahci_platform_disable_resources(hpriv);
-	ahci_put_clks(hpriv);
+	ahci_platform_put_resources(hpriv);
 }
 
 #ifdef CONFIG_PM_SLEEP
diff --git a/include/linux/ahci_platform.h b/include/linux/ahci_platform.h
index 5e5f85e..1dc7602 100644
--- a/include/linux/ahci_platform.h
+++ b/include/linux/ahci_platform.h
@@ -20,7 +20,13 @@
 struct device;
 struct ata_port_info;
 struct ahci_host_priv;
+struct platform_device;
 
+/*
+ * Note ahci_platform_data is deprecated. New drivers which need to override
+ * any of these, should instead declare there own platform_driver struct, and
+ * use ahci_platform* functions in their own probe, suspend and resume methods.
+ */
 struct ahci_platform_data {
 	int (*init)(struct device *dev, struct ahci_host_priv *hpriv);
 	void (*exit)(struct device *dev);
@@ -35,5 +41,13 @@ int ahci_platform_enable_clks(struct ahci_host_priv *hpriv);
 void ahci_platform_disable_clks(struct ahci_host_priv *hpriv);
 int ahci_platform_enable_resources(struct ahci_host_priv *hpriv);
 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv);
+struct ahci_host_priv *ahci_platform_get_resources(
+	struct platform_device *pdev);
+void ahci_platform_put_resources(struct ahci_host_priv *hpriv);
+int ahci_platform_init_host(struct platform_device *pdev,
+			    struct ahci_host_priv *hpriv,
+			    const struct ata_port_info *pi_template,
+			    unsigned int force_port_map,
+			    unsigned int mask_port_map);
 
 #endif /* _AHCI_PLATFORM_H */
-- 
1.8.5.3