MIPS: Alchemy: irda: use clk framework

Test the existence of the irda_clk clock object, use it to en/dis-
able it when date is being transferred.

Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
Cc: Linux-MIPS <linux-mips@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/7470/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 46 insertions, 2 deletions

diff --git a/drivers/net/irda/au1k_ir.c b/drivers/net/irda/au1k_ir.c
index 5f91e3e01c04..aab2cf72d025 100644
--- a/drivers/net/irda/au1k_ir.c
+++ b/drivers/net/irda/au1k_ir.c
@@ -18,6 +18,7 @@
  *  with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
+#include <linux/clk.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/interrupt.h>
@@ -175,6 +176,7 @@ struct au1k_private {
 
         struct resource *ioarea;
         struct au1k_irda_platform_data *platdata;
+        struct clk *irda_clk;
 };
 
 static int qos_mtt_bits = 0x07;  /* 1 ms or more */
@@ -514,9 +516,39 @@ static irqreturn_t au1k_irda_interrupt(int dummy, void *dev_id)
 static int au1k_init(struct net_device *dev)
 {
         struct au1k_private *aup = netdev_priv(dev);
-        u32 enable, ring_address;
+        u32 enable, ring_address, phyck;
+        struct clk *c;
         int i;
 
+        c = clk_get(NULL, "irda_clk");
+        if (IS_ERR(c))
+                return PTR_ERR(c);
+        i = clk_prepare_enable(c);
+        if (i) {
+                clk_put(c);
+                return i;
+        }
+
+        switch (clk_get_rate(c)) {
+        case 40000000:
+                phyck = IR_PHYCLK_40MHZ;
+                break;
+        case 48000000:
+                phyck = IR_PHYCLK_48MHZ;
+                break;
+        case 56000000:
+                phyck = IR_PHYCLK_56MHZ;
+                break;
+        case 64000000:
+                phyck = IR_PHYCLK_64MHZ;
+                break;
+        default:
+                clk_disable_unprepare(c);
+                clk_put(c);
+                return -EINVAL;
+        }
+        aup->irda_clk = c;
+
         enable = IR_HC | IR_CE | IR_C;
 #ifndef CONFIG_CPU_LITTLE_ENDIAN
         enable |= IR_BE;
@@ -545,7 +577,7 @@ static int au1k_init(struct net_device *dev)
         irda_write(aup, IR_RING_SIZE,
                                 (RING_SIZE_64 << 8) | (RING_SIZE_64 << 12));
 
-        irda_write(aup, IR_CONFIG_2, IR_PHYCLK_48MHZ | IR_ONE_PIN);
+        irda_write(aup, IR_CONFIG_2, phyck | IR_ONE_PIN);
         irda_write(aup, IR_RING_ADDR_CMPR, 0);
 
         au1k_irda_set_speed(dev, 9600);
@@ -619,6 +651,9 @@ static int au1k_irda_stop(struct net_device *dev)
         free_irq(aup->irq_tx, dev);
         free_irq(aup->irq_rx, dev);
 
+        clk_disable_unprepare(aup->irda_clk);
+        clk_put(aup->irda_clk);
+
         return 0;
 }
 
@@ -853,6 +888,7 @@ static int au1k_irda_probe(struct platform_device *pdev)
         struct au1k_private *aup;
         struct net_device *dev;
         struct resource *r;
+        struct clk *c;
         int err;
 
         dev = alloc_irdadev(sizeof(struct au1k_private));
@@ -886,6 +922,14 @@ static int au1k_irda_probe(struct platform_device *pdev)
         if (!aup->ioarea)
                 goto out;
 
+        /* bail out early if clock doesn't exist */
+        c = clk_get(NULL, "irda_clk");
+        if (IS_ERR(c)) {
+                err = PTR_ERR(c);
+                goto out;
+        }
+        clk_put(c);
+
         aup->iobase = ioremap_nocache(r->start, resource_size(r));
         if (!aup->iobase)
                 goto out2;