clk: versatile-icst: convert to use regmap
Instead of passing around register bases, pass around a regmap
in this driver. This refactoring make things so much easier when
we later want to manage an ICST that is part of a syscon.
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: linux-clk@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/clk/versatile/Kconfig b/drivers/clk/versatile/Kconfig
index fc50b62..e733385 100644
--- a/drivers/clk/versatile/Kconfig
+++ b/drivers/clk/versatile/Kconfig
@@ -1,6 +1,7 @@
config COMMON_CLK_VERSATILE
bool "Clock driver for ARM Reference designs"
depends on ARCH_INTEGRATOR || ARCH_REALVIEW || ARCH_VEXPRESS || ARM64 || COMPILE_TEST
+ select REGMAP_MMIO
---help---
Supports clocking on ARM Reference designs:
- Integrator/AP and Integrator/CP
diff --git a/drivers/clk/versatile/clk-icst.c b/drivers/clk/versatile/clk-icst.c
index 08c5ee9..80e955a 100644
--- a/drivers/clk/versatile/clk-icst.c
+++ b/drivers/clk/versatile/clk-icst.c
@@ -19,9 +19,13 @@
#include <linux/err.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
+#include <linux/regmap.h>
#include "clk-icst.h"
+/* Magic unlocking token used on all Versatile boards */
+#define VERSATILE_LOCK_VAL 0xA05F
+
/**
* struct clk_icst - ICST VCO clock wrapper
* @hw: corresponding clock hardware entry
@@ -32,8 +36,9 @@
*/
struct clk_icst {
struct clk_hw hw;
- void __iomem *vcoreg;
- void __iomem *lockreg;
+ struct regmap *map;
+ u32 vcoreg_off;
+ u32 lockreg_off;
struct icst_params *params;
unsigned long rate;
};
@@ -41,53 +46,67 @@
#define to_icst(_hw) container_of(_hw, struct clk_icst, hw)
/**
- * vco_get() - get ICST VCO settings from a certain register
- * @vcoreg: register containing the VCO settings
+ * vco_get() - get ICST VCO settings from a certain ICST
+ * @icst: the ICST clock to get
+ * @vco: the VCO struct to return the value in
*/
-static struct icst_vco vco_get(void __iomem *vcoreg)
+static int vco_get(struct clk_icst *icst, struct icst_vco *vco)
{
u32 val;
- struct icst_vco vco;
+ int ret;
- val = readl(vcoreg);
- vco.v = val & 0x1ff;
- vco.r = (val >> 9) & 0x7f;
- vco.s = (val >> 16) & 03;
- return vco;
+ ret = regmap_read(icst->map, icst->vcoreg_off, &val);
+ if (ret)
+ return ret;
+ vco->v = val & 0x1ff;
+ vco->r = (val >> 9) & 0x7f;
+ vco->s = (val >> 16) & 03;
+ return 0;
}
/**
* vco_set() - commit changes to an ICST VCO
- * @locreg: register to poke to unlock the VCO for writing
- * @vcoreg: register containing the VCO settings
- * @vco: ICST VCO parameters to commit
+ * @icst: the ICST clock to set
+ * @vco: the VCO struct to set the changes from
*/
-static void vco_set(void __iomem *lockreg,
- void __iomem *vcoreg,
- struct icst_vco vco)
+static int vco_set(struct clk_icst *icst, struct icst_vco vco)
{
u32 val;
+ int ret;
- val = readl(vcoreg) & ~0x7ffff;
+ ret = regmap_read(icst->map, icst->vcoreg_off, &val);
+ if (ret)
+ return ret;
val |= vco.v | (vco.r << 9) | (vco.s << 16);
/* This magic unlocks the VCO so it can be controlled */
- writel(0xa05f, lockreg);
- writel(val, vcoreg);
+ ret = regmap_write(icst->map, icst->lockreg_off, VERSATILE_LOCK_VAL);
+ if (ret)
+ return ret;
+ ret = regmap_write(icst->map, icst->vcoreg_off, val);
+ if (ret)
+ return ret;
/* This locks the VCO again */
- writel(0, lockreg);
+ ret = regmap_write(icst->map, icst->lockreg_off, 0);
+ if (ret)
+ return ret;
+ return 0;
}
-
static unsigned long icst_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_icst *icst = to_icst(hw);
struct icst_vco vco;
+ int ret;
if (parent_rate)
icst->params->ref = parent_rate;
- vco = vco_get(icst->vcoreg);
+ ret = vco_get(icst, &vco);
+ if (ret) {
+ pr_err("ICST: could not get VCO setting\n");
+ return 0;
+ }
icst->rate = icst_hz(icst->params, vco);
return icst->rate;
}
@@ -112,8 +131,7 @@
icst->params->ref = parent_rate;
vco = icst_hz_to_vco(icst->params, rate);
icst->rate = icst_hz(icst->params, vco);
- vco_set(icst->lockreg, icst->vcoreg, vco);
- return 0;
+ return vco_set(icst, vco);
}
static const struct clk_ops icst_ops = {
@@ -132,6 +150,11 @@
struct clk_icst *icst;
struct clk_init_data init;
struct icst_params *pclone;
+ struct regmap_config icst_regmap_conf = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ };
icst = kzalloc(sizeof(struct clk_icst), GFP_KERNEL);
if (!icst) {
@@ -151,10 +174,19 @@
init.flags = CLK_IS_ROOT;
init.parent_names = (parent_name ? &parent_name : NULL);
init.num_parents = (parent_name ? 1 : 0);
+ icst->map = regmap_init_mmio(dev, base, &icst_regmap_conf);
+ if (IS_ERR(icst->map)) {
+ int ret;
+
+ pr_err("could not initialize ICST regmap\n");
+ ret = PTR_ERR(icst->map);
+ kfree(icst);
+ return ERR_PTR(ret);
+ }
icst->hw.init = &init;
icst->params = pclone;
- icst->vcoreg = base + desc->vco_offset;
- icst->lockreg = base + desc->lock_offset;
+ icst->vcoreg_off = desc->vco_offset;
+ icst->lockreg_off = desc->lock_offset;
clk = clk_register(dev, &icst->hw);
if (IS_ERR(clk)) {