ARM: LPC32xx: ADC support for mach-lpc32xx

This patch adds the mach specific support for the LPC32XX ADC driver (the
latter being already in staging/iio)

Signed-off-by: Roland Stigge <stigge@antcom.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 36 insertions, 0 deletions

diff --git a/arch/arm/mach-lpc32xx/clock.c b/arch/arm/mach-lpc32xx/clock.c
index 1e027514096d..473015ac07bd 100644
--- a/arch/arm/mach-lpc32xx/clock.c
+++ b/arch/arm/mach-lpc32xx/clock.c
@@ -719,6 +719,41 @@ static struct clk clk_tsc = {
         .get_rate       = local_return_parent_rate,
 };
 
+static int adc_onoff_enable(struct clk *clk, int enable)
+{
+        u32 tmp;
+        u32 divider;
+
+        /* Use PERIPH_CLOCK */
+        tmp = __raw_readl(LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
+        tmp |= LPC32XX_CLKPWR_ADCCTRL1_PCLK_SEL;
+        /*
+         * Set clock divider so that we have equal to or less than
+         * 4.5MHz clock at ADC
+         */
+        divider = clk->get_rate(clk) / 4500000 + 1;
+        tmp |= divider;
+        __raw_writel(tmp, LPC32XX_CLKPWR_ADC_CLK_CTRL_1);
+
+        /* synchronize rate of this clock w/ actual HW setting */
+        clk->rate = clk->get_rate(clk->parent) / divider;
+
+        if (enable == 0)
+                __raw_writel(0, clk->enable_reg);
+        else
+                __raw_writel(clk->enable_mask, clk->enable_reg);
+
+        return 0;
+}
+
+static struct clk clk_adc = {
+        .parent         = &clk_pclk,
+        .enable         = adc_onoff_enable,
+        .enable_reg     = LPC32XX_CLKPWR_ADC_CLK_CTRL,
+        .enable_mask    = LPC32XX_CLKPWR_ADC32CLKCTRL_CLK_EN,
+        .get_rate       = local_return_parent_rate,
+};
+
 static int mmc_onoff_enable(struct clk *clk, int enable)
 {
         u32 tmp;
@@ -1075,6 +1110,7 @@ static struct clk_lookup lookups[] = {
         _REGISTER_CLOCK("dev:ssp1", NULL, clk_ssp1)
         _REGISTER_CLOCK("lpc32xx_keys.0", NULL, clk_kscan)
         _REGISTER_CLOCK("lpc32xx-nand.0", "nand_ck", clk_nand)
+        _REGISTER_CLOCK("lpc32xx-adc", NULL, clk_adc)
         _REGISTER_CLOCK("tbd", "i2s0_ck", clk_i2s0)
         _REGISTER_CLOCK("tbd", "i2s1_ck", clk_i2s1)
         _REGISTER_CLOCK("ts-lpc32xx", NULL, clk_tsc)