mfd: Add initial db8500 prcmu register access api

This patch adds an initial PRCMU register access API, which
for now should only be used for a very limited set of registers.

The idea about this API is that we split the PRCMU driver in
one part that deals with interaction with the PRCMU firmware
and one part that simply provide write accessors in the PRCMU
register range. The latter are just a collection of registers
exposed in the PRCMU register range for various purposes and
not related to the PRCMU firmware.

Currently we support some limited GPIO, SPI and UART settings
through this API.

Signed-off-by: Mattias Nilsson <mattias.i.nilsson@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

1 files changed, 17 insertions, 19 deletions

diff --git a/drivers/mfd/db8500-prcmu.c b/drivers/mfd/db8500-prcmu.c
index 0ee801582d82..128b5f4a4fb0 100644
--- a/drivers/mfd/db8500-prcmu.c
+++ b/drivers/mfd/db8500-prcmu.c
@@ -417,8 +417,8 @@ static struct {
 static atomic_t ac_wake_req_state = ATOMIC_INIT(0);
 
 /* Spinlocks */
+static DEFINE_SPINLOCK(prcmu_lock);
 static DEFINE_SPINLOCK(clkout_lock);
-static DEFINE_SPINLOCK(gpiocr_lock);
 
 /* Global var to runtime determine TCDM base for v2 or v1 */
 static __iomem void *tcdm_base;
@@ -639,32 +639,30 @@ int db8500_prcmu_set_display_clocks(void)
 	return 0;
 }
 
-/**
- * prcmu_enable_spi2 - Enables pin muxing for SPI2 on OtherAlternateC1.
- */
-void prcmu_enable_spi2(void)
+u32 db8500_prcmu_read(unsigned int reg)
+{
+	return readl(_PRCMU_BASE + reg);
+}
+
+void db8500_prcmu_write(unsigned int reg, u32 value)
 {
-	u32 reg;
 	unsigned long flags;
 
-	spin_lock_irqsave(&gpiocr_lock, flags);
-	reg = readl(PRCM_GPIOCR);
-	writel(reg | PRCM_GPIOCR_SPI2_SELECT, PRCM_GPIOCR);
-	spin_unlock_irqrestore(&gpiocr_lock, flags);
+	spin_lock_irqsave(&prcmu_lock, flags);
+	writel(value, (_PRCMU_BASE + reg));
+	spin_unlock_irqrestore(&prcmu_lock, flags);
 }
 
-/**
- * prcmu_disable_spi2 - Disables pin muxing for SPI2 on OtherAlternateC1.
- */
-void prcmu_disable_spi2(void)
+void db8500_prcmu_write_masked(unsigned int reg, u32 mask, u32 value)
 {
-	u32 reg;
+	u32 val;
 	unsigned long flags;
 
-	spin_lock_irqsave(&gpiocr_lock, flags);
-	reg = readl(PRCM_GPIOCR);
-	writel(reg & ~PRCM_GPIOCR_SPI2_SELECT, PRCM_GPIOCR);
-	spin_unlock_irqrestore(&gpiocr_lock, flags);
+	spin_lock_irqsave(&prcmu_lock, flags);
+	val = readl(_PRCMU_BASE + reg);
+	val = ((val & ~mask) | (value & mask));
+	writel(val, (_PRCMU_BASE + reg));
+	spin_unlock_irqrestore(&prcmu_lock, flags);
 }
 
 struct prcmu_fw_version *prcmu_get_fw_version(void)