Basic PWM driver for AVR32 and AT91

PWM device setup, and a simple PWM driver exposing a programming interface
giving access to each channel's full capabilities.  Note that this doesn't
support starting several channels in synch.

[hskinnemoen@atmel.com: allocate platform device dynamically]
[hskinnemoen@atmel.com: Kconfig fix]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Andrew Victor <linux@maxim.org.za>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/avr32/mach-at32ap/at32ap700x.c

@@ -1185,6 +1185,59 @@ at32_add_device_lcdc(unsigned int id, struct atmel_lcdfb_info *data,
 }
 #endif
 
+/* --------------------------------------------------------------------
+ *  PWM
+ * -------------------------------------------------------------------- */
+static struct resource atmel_pwm0_resource[] __initdata = {
+	PBMEM(0xfff01400),
+	IRQ(24),
+};
+static struct clk atmel_pwm0_mck = {
+	.name		= "mck",
+	.parent		= &pbb_clk,
+	.mode		= pbb_clk_mode,
+	.get_rate	= pbb_clk_get_rate,
+	.index		= 5,
+};
+
+struct platform_device *__init at32_add_device_pwm(u32 mask)
+{
+	struct platform_device *pdev;
+
+	if (!mask)
+		return NULL;
+
+	pdev = platform_device_alloc("atmel_pwm", 0);
+	if (!pdev)
+		return NULL;
+
+	if (platform_device_add_resources(pdev, atmel_pwm0_resource,
+				ARRAY_SIZE(atmel_pwm0_resource)))
+		goto out_free_pdev;
+
+	if (platform_device_add_data(pdev, &mask, sizeof(mask)))
+		goto out_free_pdev;
+
+	if (mask & (1 << 0))
+		select_peripheral(PA(28), PERIPH_A, 0);
+	if (mask & (1 << 1))
+		select_peripheral(PA(29), PERIPH_A, 0);
+	if (mask & (1 << 2))
+		select_peripheral(PA(21), PERIPH_B, 0);
+	if (mask & (1 << 3))
+		select_peripheral(PA(22), PERIPH_B, 0);
+
+	atmel_pwm0_mck.dev = &pdev->dev;
+
+	platform_device_add(pdev);
+
+	return pdev;
+
+out_free_pdev:
+	platform_device_put(pdev);
+	return NULL;
+}
+
 /* --------------------------------------------------------------------
  *  SSC
  * -------------------------------------------------------------------- */
@@ -1646,6 +1699,7 @@ struct clk *at32_clock_list[] = {
 	&atmel_usart1_usart,
 	&atmel_usart2_usart,
 	&atmel_usart3_usart,
+	&atmel_pwm0_mck,
 #if defined(CONFIG_CPU_AT32AP7000)
 	&macb0_hclk,
 	&macb0_pclk,

drivers/misc/Kconfig

@@ -13,6 +13,15 @@ menuconfig MISC_DEVICES
 
 if MISC_DEVICES
 
+config ATMEL_PWM
+	tristate "Atmel AT32/AT91 PWM support"
+	depends on AVR32 || ARCH_AT91
+	help
+	  This option enables device driver support for the PWM channels
+	  on certain Atmel prcoessors.  Pulse Width Modulation is used for
+	  purposes including software controlled power-efficent backlights
+	  on LCD displays, motor control, and waveform generation.
+
 config IBM_ASM
 	tristate "Device driver for IBM RSA service processor"
 	depends on X86 && PCI && INPUT && EXPERIMENTAL

drivers/misc/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_HDPU_FEATURES)	+= hdpuftrs/
 obj-$(CONFIG_MSI_LAPTOP)     += msi-laptop.o
 obj-$(CONFIG_ACER_WMI)     += acer-wmi.o
 obj-$(CONFIG_ASUS_LAPTOP)     += asus-laptop.o
+obj-$(CONFIG_ATMEL_PWM)		+= atmel_pwm.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
 obj-$(CONFIG_TC1100_WMI)	+= tc1100-wmi.o
 obj-$(CONFIG_LKDTM)		+= lkdtm.o