[RFC v3 06/13] ahci-platform: Add support for devices with more then 1 clock
Hans de Goede
hdegoede at redhat.com
Sat Jan 18 18:48:48 EST 2014
The allwinner-sun4i AHCI controller needs 2 clocks to be enabled and the
imx AHCI controller needs 3 clocks to be enabled.
Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
.../devicetree/bindings/ata/ahci-platform.txt | 1 +
drivers/ata/ahci.h | 3 +-
drivers/ata/ahci_platform.c | 95 +++++++++++++++-------
3 files changed, 67 insertions(+), 32 deletions(-)
diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
index 89de156..3ced07d 100644
--- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
+++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
@@ -10,6 +10,7 @@ Required properties:
Optional properties:
- dma-coherent : Present if dma operations are coherent
+- clocks : a list of phandle + clock specifier pairs
Example:
sata at ffe08000 {
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 8f60f33..7950b3a 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -52,6 +52,7 @@
enum {
AHCI_MAX_PORTS = 32,
AHCI_MAX_SG = 168, /* hardware max is 64K */
+ AHCI_MAX_CLKS = 3,
AHCI_DMA_BOUNDARY = 0xffffffff,
AHCI_MAX_CMDS = 32,
AHCI_CMD_SZ = 32,
@@ -321,7 +322,7 @@ struct ahci_host_priv {
u32 em_loc; /* enclosure management location */
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 clk *clks[AHCI_MAX_CLKS]; /* Optional */
void *plat_data; /* Other platform data */
/* Optional ahci_start_engine override */
void (*start_engine)(struct ata_port *ap);
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 33ac7a4..75a3d47 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -87,6 +87,42 @@ static struct scsi_host_template ahci_platform_sht = {
AHCI_SHT("ahci_platform"),
};
+static int ahci_enable_clks(struct device *dev, struct ahci_host_priv *hpriv)
+{
+ int c, rc;
+
+ for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
+ rc = clk_prepare_enable(hpriv->clks[c]);
+ if (rc) {
+ dev_err(dev, "clock prepare enable failed");
+ goto disable_unprepare_clk;
+ }
+ }
+ return 0;
+
+disable_unprepare_clk:
+ while (--c >= 0)
+ clk_disable_unprepare(hpriv->clks[c]);
+ return rc;
+}
+
+static void ahci_disable_clks(struct ahci_host_priv *hpriv)
+{
+ int c;
+
+ for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
+ if (hpriv->clks[c])
+ clk_disable_unprepare(hpriv->clks[c]);
+}
+
+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 device *dev = &pdev->dev;
@@ -97,10 +133,8 @@ static int ahci_probe(struct platform_device *pdev)
struct ahci_host_priv *hpriv;
struct ata_host *host;
struct resource *mem;
- int irq;
- int n_ports;
- int i;
- int rc;
+ struct clk *clk;
+ int i, irq, max_clk, n_ports, rc;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem) {
@@ -131,17 +165,26 @@ static int ahci_probe(struct platform_device *pdev)
return -ENOMEM;
}
- hpriv->clk = clk_get(dev, NULL);
- if (IS_ERR(hpriv->clk)) {
- dev_err(dev, "can't get clock\n");
- } else {
- rc = clk_prepare_enable(hpriv->clk);
- if (rc) {
- dev_err(dev, "clock prepare enable failed");
- goto free_clk;
+ max_clk = dev->of_node ? AHCI_MAX_CLKS : 1;
+ for (i = 0; i < max_clk; i++) {
+ if (i == 0)
+ clk = clk_get(dev, NULL); /* For old platform init */
+ else
+ clk = of_clk_get(dev->of_node, i);
+
+ if (IS_ERR(clk)) {
+ rc = PTR_ERR(clk);
+ if (rc == -EPROBE_DEFER)
+ goto free_clk;
+ break;
}
+ hpriv->clks[i] = clk;
}
+ rc = ahci_enable_clks(dev, hpriv);
+ if (rc)
+ goto free_clk;
+
/*
* Some platforms might need to prepare for mmio region access,
* which could be done in the following init call. So, the mmio
@@ -222,11 +265,9 @@ pdata_exit:
if (pdata && pdata->exit)
pdata->exit(dev);
disable_unprepare_clk:
- if (!IS_ERR(hpriv->clk))
- clk_disable_unprepare(hpriv->clk);
+ ahci_disable_clks(hpriv);
free_clk:
- if (!IS_ERR(hpriv->clk))
- clk_put(hpriv->clk);
+ ahci_put_clks(hpriv);
return rc;
}
@@ -239,10 +280,8 @@ static void ahci_host_stop(struct ata_host *host)
if (pdata && pdata->exit)
pdata->exit(dev);
- if (!IS_ERR(hpriv->clk)) {
- clk_disable_unprepare(hpriv->clk);
- clk_put(hpriv->clk);
- }
+ ahci_disable_clks(hpriv);
+ ahci_put_clks(hpriv);
}
#ifdef CONFIG_PM_SLEEP
@@ -277,8 +316,7 @@ static int ahci_suspend(struct device *dev)
if (pdata && pdata->suspend)
pdata->suspend(dev);
- if (!IS_ERR(hpriv->clk))
- clk_disable_unprepare(hpriv->clk);
+ ahci_disable_clks(hpriv);
return 0;
}
@@ -290,13 +328,9 @@ static int ahci_resume(struct device *dev)
struct ahci_host_priv *hpriv = host->private_data;
int rc;
- if (!IS_ERR(hpriv->clk)) {
- rc = clk_prepare_enable(hpriv->clk);
- if (rc) {
- dev_err(dev, "clock prepare enable failed");
- return rc;
- }
- }
+ rc = ahci_enable_clks(dev, hpriv);
+ if (rc)
+ return rc;
if (pdata && pdata->resume) {
rc = pdata->resume(dev);
@@ -320,8 +354,7 @@ pdata_suspend:
if (pdata && pdata->suspend)
pdata->suspend(dev);
disable_unprepare_clk:
- if (!IS_ERR(hpriv->clk))
- clk_disable_unprepare(hpriv->clk);
+ ahci_disable_clks(hpriv);
return rc;
}
--
1.8.4.2
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