NUC900: Add platform support for nuc900 i2c driver

PATCH Superseded Wan ZongShun 1 participant 1 message Jun 13, 2010

Subsystems (3)

Arm (32-bit) Arm sub-architectures I2C subsystem host drivers

lore

Share & tools

lore

Wan ZongShun

author

2010-06-13 17:28 UTC #0 lore raw

PATCH 2/2 NUC900: Add platform support for nuc900 i2c driver

This patch is to add platform support for i2c driver. For get i2c work clock, I implemented the 'nuc900_get_cpuclock' api for getting cpu,apb,ahb clock.

Signed-off-by Wan ZongShun <[email protected]>

---
 arch/arm/mach-w90x900/cpu.c |   43 +++++++++++++++++++++++++++++++++
 arch/arm/mach-w90x900/cpu.h |    3 +-
 arch/arm/mach-w90x900/dev.c |   56 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 101 insertions(+), 1 deletions(-)

arch/arm/mach-w90x900/cpu.c +43 -0

index 642207e..2396548 100644
@@ -195,6 +195,49 @@ static int __init nuc900_set_cpufreq(char *str)
 
 __setup("cpufreq=", nuc900_set_cpufreq);
 
+void nuc900_get_cpuclock(unsigned int *cpuclk_khz,
+			unsigned int *ahbclk_khz, unsigned int *apbclk_khz) {
+
+	int ahbspeed = 0, apbspeed = 0, cpuspeed = 0;
+
+	if (cpuclk_khz) {
+		cpuspeed = __raw_readl(REG_PLLCON0);
+		if (cpuspeed == PLL_200MHZ)
+			cpuspeed = 200 * 1000;
+		else if (cpuspeed == PLL_166MHZ)
+			cpuspeed = 166 * 1000;
+		else if (cpuspeed == PLL_120MHZ)
+			cpuspeed = 120 * 1000;
+		else if (cpuspeed == PLL_100MHZ)
+			cpuspeed = 100 * 1000;
+		else if (cpuspeed == PLL_66MHZ)
+			cpuspeed = 66 * 1000;
+		else
+			printk(KERN_ERR "Can not read true cpuspeed!\n");
+		*cpuclk_khz = cpuspeed;
+	}
+
+	if (ahbclk_khz) {
+		ahbspeed = (__raw_readl(REG_CLKDIV) >> 24) & 0x03;
+		if (ahbspeed == AHB_CPUCLK_1_1)
+			ahbspeed = cpuspeed;
+		else if (ahbspeed == AHB_CPUCLK_1_2)
+			ahbspeed = cpuspeed / 2;
+		else
+			printk(KERN_ERR "Can not read true ahbspeed!\n");
+		*ahbclk_khz = ahbspeed;
+	}
+
+	if (apbclk_khz) {
+		apbspeed = (__raw_readl(REG_CLKDIV) >> 26) & 0x03;
+		if (apbspeed == APB_AHB_1_2)
+			apbspeed = ahbspeed / 2;
+		else
+			printk(KERN_ERR "Can not read true apbspeed!\n");
+		*apbclk_khz = apbspeed;
+	}
+}
+
 /*Init NUC900 evb io*/
 
 void __init nuc900_map_io(struct map_desc *mach_desc, int mach_size)

arch/arm/mach-w90x900/cpu.h +2 -1

index f8730b6..00217ad 100644
@@ -49,7 +49,8 @@ extern void nuc900_clock_source(struct device *dev, unsigned char *src);
 extern void nuc900_init_clocks(void);
 extern void nuc900_map_io(struct map_desc *mach_desc, int mach_size);
 extern void nuc900_board_init(struct platform_device **device, int size);
-
+extern void nuc900_get_cpuclock(unsigned int *cpuclk_khz,
+			unsigned int *ahbclk_khz, unsigned int *apbclk_khz);
 /* for either public between 910 and 920, or between 920 and 950 */
 
 extern struct platform_device nuc900_serial_device;

arch/arm/mach-w90x900/dev.c +56 -0

80 lines not on this page · raw message

Signature · 1 line

1.6.3.3