clk: at91: make use of syscon/regmap internally

Use the regmap coming from syscon to access the registers instead of using
pmc_read/pmc_write. This allows to avoid passing the at91_pmc structure to
the child nodes of the PMC.

The final benefit is to have each clock register itself instead of having
to iterate over the children.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

1 files changed, 37 insertions, 23 deletions

diff --git a/drivers/clk/at91/clk-system.c b/drivers/clk/at91/clk-system.c
index 3f5314344286..0593adf1bf4b 100644
--- a/drivers/clk/at91/clk-system.c
+++ b/drivers/clk/at91/clk-system.c
@@ -19,6 +19,8 @@
 #include <linux/interrupt.h>
 #include <linux/wait.h>
 #include <linux/sched.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
 
 #include "pmc.h"
 
@@ -29,7 +31,7 @@
 #define to_clk_system(hw) container_of(hw, struct clk_system, hw)
 struct clk_system {
 	struct clk_hw hw;
-	struct at91_pmc *pmc;
+	struct regmap *regmap;
 	unsigned int irq;
 	wait_queue_head_t wait;
 	u8 id;
@@ -49,24 +51,32 @@ static irqreturn_t clk_system_irq_handler(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
+static inline bool clk_system_ready(struct regmap *regmap, int id)
+{
+	unsigned int status;
+
+	regmap_read(regmap, AT91_PMC_SR, &status);
+
+	return status & (1 << id) ? 1 : 0;
+}
+
 static int clk_system_prepare(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
-	u32 mask = 1 << sys->id;
 
-	pmc_write(pmc, AT91_PMC_SCER, mask);
+	regmap_write(sys->regmap, AT91_PMC_SCER, 1 << sys->id);
 
 	if (!is_pck(sys->id))
 		return 0;
 
-	while (!(pmc_read(pmc, AT91_PMC_SR) & mask)) {
+	while (!clk_system_ready(sys->regmap, sys->id)) {
 		if (sys->irq) {
 			enable_irq(sys->irq);
 			wait_event(sys->wait,
-				   pmc_read(pmc, AT91_PMC_SR) & mask);
-		} else
+				   clk_system_ready(sys->regmap, sys->id));
+		} else {
 			cpu_relax();
+		}
 	}
 	return 0;
 }
@@ -74,23 +84,26 @@ static int clk_system_prepare(struct clk_hw *hw)
 static void clk_system_unprepare(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
 
-	pmc_write(pmc, AT91_PMC_SCDR, 1 << sys->id);
+	regmap_write(sys->regmap, AT91_PMC_SCDR, 1 << sys->id);
 }
 
 static int clk_system_is_prepared(struct clk_hw *hw)
 {
 	struct clk_system *sys = to_clk_system(hw);
-	struct at91_pmc *pmc = sys->pmc;
+	unsigned int status;
+
+	regmap_read(sys->regmap, AT91_PMC_SCSR, &status);
 
-	if (!(pmc_read(pmc, AT91_PMC_SCSR) & (1 << sys->id)))
+	if (!(status & (1 << sys->id)))
 		return 0;
 
 	if (!is_pck(sys->id))
 		return 1;
 
-	return !!(pmc_read(pmc, AT91_PMC_SR) & (1 << sys->id));
+	regmap_read(sys->regmap, AT91_PMC_SR, &status);
+
+	return status & (1 << sys->id) ? 1 : 0;
 }
 
 static const struct clk_ops system_ops = {
@@ -100,7 +113,7 @@ static const struct clk_ops system_ops = {
 };
 
 static struct clk * __init
-at91_clk_register_system(struct at91_pmc *pmc, const char *name,
+at91_clk_register_system(struct regmap *regmap, const char *name,
 			 const char *parent_name, u8 id, int irq)
 {
 	struct clk_system *sys;
@@ -123,7 +136,7 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name,
 
 	sys->id = id;
 	sys->hw.init = &init;
-	sys->pmc = pmc;
+	sys->regmap = regmap;
 	sys->irq = irq;
 	if (irq) {
 		init_waitqueue_head(&sys->wait);
@@ -146,8 +159,7 @@ at91_clk_register_system(struct at91_pmc *pmc, const char *name,
 	return clk;
 }
 
-static void __init
-of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
+static void __init of_at91rm9200_clk_sys_setup(struct device_node *np)
 {
 	int num;
 	int irq = 0;
@@ -156,11 +168,16 @@ of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
 	const char *name;
 	struct device_node *sysclknp;
 	const char *parent_name;
+	struct regmap *regmap;
 
 	num = of_get_child_count(np);
 	if (num > (SYSTEM_MAX_ID + 1))
 		return;
 
+	regmap = syscon_node_to_regmap(of_get_parent(np));
+	if (IS_ERR(regmap))
+		return;
+
 	for_each_child_of_node(np, sysclknp) {
 		if (of_property_read_u32(sysclknp, "reg", &id))
 			continue;
@@ -173,16 +190,13 @@ of_at91_clk_sys_setup(struct device_node *np, struct at91_pmc *pmc)
 
 		parent_name = of_clk_get_parent_name(sysclknp, 0);
 
-		clk = at91_clk_register_system(pmc, name, parent_name, id, irq);
+		clk = at91_clk_register_system(regmap, name, parent_name, id,
+					       irq);
 		if (IS_ERR(clk))
 			continue;
 
 		of_clk_add_provider(sysclknp, of_clk_src_simple_get, clk);
 	}
 }
-
-void __init of_at91rm9200_clk_sys_setup(struct device_node *np,
-					struct at91_pmc *pmc)
-{
-	of_at91_clk_sys_setup(np, pmc);
-}
+CLK_OF_DECLARE(at91rm9200_clk_sys, "atmel,at91rm9200-clk-system",
+	       of_at91rm9200_clk_sys_setup);