[PATCH v10 4/5] [powerpc] Add flexcan device support for p1010rdb.

[Robin Holt]

I added a simple clock source for the p1010rdb so the flexcan driver
could determine a clock frequency.  The p1010 can device only has an
oscillator of system bus frequency divided by 2.

Signed-off-by: Robin Holt <holt at sgi.com>
Acked-by: Marc Kleine-Budde <mkl at pengutronix.de>,
Acked-by: Wolfgang Grandegger <wg at grandegger.com>,
To: U Bhaskar-B22300 <B22300 at freescale.com>
Cc: socketcan-core at lists.berlios.de,
Cc: netdev at vger.kernel.org,
Cc: PPC list <linuxppc-dev at lists.ozlabs.org>
Cc: Kumar Gala <galak at kernel.crashing.org>
---
 arch/powerpc/platforms/85xx/Kconfig    |    2 +
 arch/powerpc/platforms/85xx/Makefile   |    2 +
 arch/powerpc/platforms/85xx/clock.c    |   53 ++++++++++++++++++++++++++++++++
 arch/powerpc/platforms/85xx/p1010rdb.c |    8 +++++
 4 files changed, 65 insertions(+), 0 deletions(-)
 create mode 100644 arch/powerpc/platforms/85xx/clock.c

diff --git a/arch/powerpc/platforms/85xx/Kconfig b/arch/powerpc/platforms/85xx/Kconfig
index 498534c..c4304ae 100644
--- a/arch/powerpc/platforms/85xx/Kconfig
+++ b/arch/powerpc/platforms/85xx/Kconfig
@@ -70,6 +70,8 @@ config MPC85xx_RDB
 config P1010_RDB
 	bool "Freescale P1010RDB"
 	select DEFAULT_UIMAGE
+	select HAVE_CAN_FLEXCAN if NET && CAN
+	select PPC_CLOCK if CAN_FLEXCAN
 	help
 	  This option enables support for the MPC85xx RDB (P1010 RDB) board
 
diff --git a/arch/powerpc/platforms/85xx/Makefile b/arch/powerpc/platforms/85xx/Makefile
index a971b32..cc7f381 100644
--- a/arch/powerpc/platforms/85xx/Makefile
+++ b/arch/powerpc/platforms/85xx/Makefile
@@ -3,6 +3,8 @@
 #
 obj-$(CONFIG_SMP) += smp.o
 
+obj-$(CONFIG_PPC_CLOCK)   += clock.o
+
 obj-$(CONFIG_MPC8540_ADS) += mpc85xx_ads.o
 obj-$(CONFIG_MPC8560_ADS) += mpc85xx_ads.o
 obj-$(CONFIG_MPC85xx_CDS) += mpc85xx_cds.o
diff --git a/arch/powerpc/platforms/85xx/clock.c b/arch/powerpc/platforms/85xx/clock.c
new file mode 100644
index 0000000..16fae04
--- /dev/null
+++ b/arch/powerpc/platforms/85xx/clock.c
@@ -0,0 +1,53 @@
+/*
+ * Copyright 2011 SGI, inc.
+ *
+ * This code is licensed for use under the GPL V2 as published by
+ * the Free Software Foundation.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/of.h>
+
+#include <asm/clk_interface.h>
+
+#include <sysdev/fsl_soc.h>
+
+/*
+ * p1010 needs to provide a clock source for the flexcan driver. The
+ * oscillator for the p1010 processor is only ever the system clock / 2.
+ */
+
+static struct clk *mpc85xx_clk_get(struct device *dev, const char *id)
+{
+	if (!dev)
+		return ERR_PTR(-ENOENT);
+
+        if (!dev->of_node ||
+            !of_device_is_compatible(dev->of_node, "fsl,flexcan"))
+                return ERR_PTR(-ENOENT);
+
+	return NULL;
+}
+
+static void mpc85xx_clk_put(struct clk *clk)
+{
+	return;
+}
+
+static unsigned long mpc85xx_clk_get_rate(struct clk *clk)
+{
+	return fsl_get_sys_freq() / 2;
+}
+
+static struct clk_interface mpc85xx_clk_functions = {
+	.clk_get = mpc85xx_clk_get,
+	.clk_get_rate = mpc85xx_clk_get_rate,
+	.clk_put = mpc85xx_clk_put,
+};
+
+void __init mpc85xx_clk_init(void)
+{
+	clk_functions = mpc85xx_clk_functions;
+}
+
diff --git a/arch/powerpc/platforms/85xx/p1010rdb.c b/arch/powerpc/platforms/85xx/p1010rdb.c
index d7387fa..5e52122 100644
--- a/arch/powerpc/platforms/85xx/p1010rdb.c
+++ b/arch/powerpc/platforms/85xx/p1010rdb.c
@@ -81,6 +81,13 @@ static void __init p1010_rdb_setup_arch(void)
 	printk(KERN_INFO "P1010 RDB board from Freescale Semiconductor\n");
 }
 
+extern void mpc85xx_clk_init(void);
+
+static void __init p1010_rdb_init(void)
+{
+	mpc85xx_clk_init();
+}
+
 static struct of_device_id __initdata p1010rdb_ids[] = {
 	{ .type = "soc", },
 	{ .compatible = "soc", },
@@ -111,6 +118,7 @@ define_machine(p1010_rdb) {
 	.name			= "P1010 RDB",
 	.probe			= p1010_rdb_probe,
 	.setup_arch		= p1010_rdb_setup_arch,
+	.init			= p1010_rdb_init,
 	.init_IRQ		= p1010_rdb_pic_init,
 #ifdef CONFIG_PCI
 	.pcibios_fixup_bus	= fsl_pcibios_fixup_bus,
-- 
1.7.2.1