SYSLINK:IPU-PM: changes in I2C to use HWspinlocks

Each i2c bus (4) is assigned to use one hwspinlock.
Those spinlocks are by default 0,1,2 and 3.
When an i2c bus is requested the number of hwspinlock is
also provided via the rcb to the requester.

Signed-off-by: Miguel Vadillo <vadillo@ti.com>
Signed-off-by: Juan Gutierrez <jgutierrez@ti.com>
Signed-off-by: Paul Hunt <hunt@ti.com>

2 files changed, 46 insertions, 14 deletions

diff --git a/drivers/dsp/syslink/ipu_pm/ipu_pm.c b/drivers/dsp/syslink/ipu_pm/ipu_pm.c
index 939a1505a67d..76f7ba73ab08 100644
--- a/drivers/dsp/syslink/ipu_pm/ipu_pm.c
+++ b/drivers/dsp/syslink/ipu_pm/ipu_pm.c
@@ -19,6 +19,7 @@
 #include <linux/module.h>
 #include <linux/cdev.h>
 #include <linux/device.h>
+#include <linux/mod_devicetable.h>
 #include <linux/fs.h>
 #include <linux/mm.h>
 #include <linux/slab.h>
@@ -120,15 +121,24 @@ static int ch, ch_aux;
 static int pm_regulator_num;
 static int return_val;
 static u32 GPTIMER_USE_MASK = 0xFFFF;
+static u32 I2C_USE_MASK = 0xFFFF;
 static u32 cam2_prev_volt;
 
-/* Gptimer assignment mapping table */
+/* Ducati Interrupt Capable Gptimers */
 static int ipu_timer_list[NUM_IPU_TIMERS] = {
 	GP_TIMER_3,
 	GP_TIMER_4,
 	GP_TIMER_9,
 	GP_TIMER_11};
 
+/* I2C spinlock assignment mapping table */
+static int i2c_spinlock_list[I2C_BUS_MAX + 1] = {
+	I2C_SL_INVAL,
+	I2C_1_SL,
+	I2C_2_SL,
+	I2C_3_SL,
+	I2C_4_SL};
+
 static char *ipu_regulator_name[REGULATOR_MAX] = {
 	"cam2pwr"};
 
@@ -612,7 +622,7 @@ static inline int ipu_pm_get_i2c_bus(int proc_id, unsigned rcb_num)
 	struct rcb_block *rcb_p;
 	struct clk *p_i2c_clk;
 	int i2c_clk_status;
-	char i2c_name[10];
+	char i2c_name[I2C_NAME_SIZE];
 
 	/* get the handle to proper ipu pm object */
 	handle = ipu_pm_get_handle(proc_id);
@@ -633,20 +643,27 @@ static inline int ipu_pm_get_i2c_bus(int proc_id, unsigned rcb_num)
 			(pm_i2c_bus_num > I2C_BUS_MAX)))
 		return PM_INVAL_NUM_I2C;
 
-	/* building the name for i2c_clk */
-	sprintf(i2c_name, "i2c%d_fck", pm_i2c_bus_num);
+	if (I2C_USE_MASK & (1 << pm_i2c_bus_num)) {
+		/* building the name for i2c_clk */
+		sprintf(i2c_name, "i2c%d_fck", pm_i2c_bus_num);
+
+		/* Request resource using PRCM API */
+		p_i2c_clk = omap_clk_get_by_name(i2c_name);
+		if (p_i2c_clk == 0)
+			return PM_NO_I2C;
+		i2c_clk_status = clk_enable(p_i2c_clk);
+		if (i2c_clk_status != 0)
+			return PM_NO_I2C;
+		/* Clear the bit in the usage mask */
+		I2C_USE_MASK &= ~(1 << pm_i2c_bus_num);
+		rcb_p->mod_base_addr = (unsigned)p_i2c_clk;
+		/* Get the HW spinlock and store it in the RCB */
+		rcb_p->data[0] = i2c_spinlock_list[pm_i2c_bus_num];
+		params->pm_i2c_bus_counter++;
 
-	/* Request resource using PRCM API */
-	p_i2c_clk = omap_clk_get_by_name(i2c_name);
-	if (p_i2c_clk == 0)
-		return PM_NO_I2C;
-	i2c_clk_status = clk_enable(p_i2c_clk);
-	if (i2c_clk_status != 0)
+		return PM_SUCCESS;
+	} else
 		return PM_NO_I2C;
-	rcb_p->mod_base_addr = (unsigned)p_i2c_clk;
-	params->pm_i2c_bus_counter++;
-
-	return PM_SUCCESS;
 }
 
 /*
@@ -847,11 +864,20 @@ static inline int ipu_pm_rel_i2c_bus(int proc_id, unsigned rcb_num)
 		return PM_INVAL_RCB_NUM;
 
 	rcb_p = (struct rcb_block *)&handle->rcb_table->rcb[rcb_num];
+	pm_i2c_bus_num = rcb_p->fill9;
 	p_i2c_clk = (struct clk *)rcb_p->mod_base_addr;
 
+	/* Check the usage mask */
+	if (I2C_USE_MASK & (1 << pm_i2c_bus_num))
+		return PM_NO_I2C;
+
 	/* Release resource using PRCM API */
 	clk_disable(p_i2c_clk);
 	rcb_p->mod_base_addr = 0;
+
+	/* Set the usage mask for reuse */
+	I2C_USE_MASK |= (1 << pm_i2c_bus_num);
+
 	params->pm_i2c_bus_counter--;
 
 	return PM_SUCCESS;
diff --git a/drivers/dsp/syslink/ipu_pm/ipu_pm.h b/drivers/dsp/syslink/ipu_pm/ipu_pm.h
index 6d1ab5d1c6ba..550fa5f00f54 100644
--- a/drivers/dsp/syslink/ipu_pm/ipu_pm.h
+++ b/drivers/dsp/syslink/ipu_pm/ipu_pm.h
@@ -109,6 +109,12 @@
 #define GP_TIMER_11 11
 #define NUM_IPU_TIMERS 4
 
+#define I2C_SL_INVAL -1
+#define I2C_1_SL 0
+#define I2C_2_SL 1
+#define I2C_3_SL 2
+#define I2C_4_SL 3
+
 #define RCB_MIN 1
 #define RCB_MAX 33