[PATCH v2 6/6] Input: olpc_apsp: enable the SP clock

[Lubomir Rintel]

Without the clock, the keyboard controller won't operate.
Tested on an OLPC XO 1.75.

Signed-off-by: Lubomir Rintel <lkund...@v3.sk>
Acked-by: Pavel Machek <pa...@ucw.cz>

---
Changes since v1:
- Disable the clock in error handling path

 drivers/input/serio/olpc_apsp.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/input/serio/olpc_apsp.c b/drivers/input/serio/olpc_apsp.c
index 8b19a47dfa46..91d6fb8d7d8d 100644
--- a/drivers/input/serio/olpc_apsp.c
+++ b/drivers/input/serio/olpc_apsp.c
@@ -23,6 +23,7 @@
 #include <linux/of.h>
 #include <linux/slab.h>
 #include <linux/delay.h>
+#include <linux/clk.h>
 
 /*
  * The OLPC XO-1.75 and XO-4 laptops do not have a hardware PS/2 controller.
@@ -74,6 +75,7 @@ struct olpc_apsp {
        struct serio *kbio;
        struct serio *padio;
        void __iomem *base;
+       struct clk *clk;
        int open_count;
        int irq;
 };
@@ -146,11 +148,17 @@ static int olpc_apsp_open(struct serio *port)
        struct olpc_apsp *priv = port->port_data;
        unsigned int tmp;
        unsigned long l;
+       int error;
 
        if (priv->open_count++ == 0) {
+               error = clk_prepare_enable(priv->clk);
+               if (error)
+                       return error;
+
                l = readl(priv->base + COMMAND_FIFO_STATUS);
                if (!(l & CMD_STS_MASK)) {
                        dev_err(priv->dev, "SP cannot accept commands.\n");
+                       clk_disable_unprepare(priv->clk);
                        return -EIO;
                }
 
@@ -171,6 +179,8 @@ static void olpc_apsp_close(struct serio *port)
                /* Disable interrupt 0 */
                tmp = readl(priv->base + PJ_INTERRUPT_MASK);
                writel(tmp | INT_0, priv->base + PJ_INTERRUPT_MASK);
+
+               clk_disable_unprepare(priv->clk);
        }
 }
 
@@ -198,6 +208,10 @@ static int olpc_apsp_probe(struct platform_device *pdev)
        if (priv->irq < 0)
                return priv->irq;
 
+       priv->clk = devm_clk_get(&pdev->dev, "sp");
+       if (IS_ERR(priv->clk))
+               return PTR_ERR(priv->clk);
+
        /* KEYBOARD */
        kb_serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
        if (!kb_serio)
-- 
2.19.1