LinuxLists.cc - [PATCH v1 0/1] clk: npcm7xx: fix base address and of_clk_get_by

2018-07-17 11:35:30

Subject: [PATCH v1 0/1] clk: npcm7xx: fix base address and of_clk_get_by_name

2018-07-17 11:33:45

Subject: [PATCH v1 1/1] clk: npcm7xx: get fixed clocks from DT

Nuvoton NPCM7XX Clock Controller
fix base address and of_clk_get_by_name error handling.
Also update error messages to be more informative.

In case clk_base allocation is erronoeous the return value is null.
Also fix handling of of_clk_get_by_name returns an error.
Print a better error message pointing to the dt-binding documention.

This patch is re-submitted since it was already pushed to main
(just the diff, without the full driver which is already in
master branch.)

Signed-off-by: Tali Perry <[email protected]>
Reviewed-by: Rob Herring <[email protected]>
Signed-off-by: Wei Yongjun <[email protected]>

---
drivers/clk/clk-npcm7xx.c | 101 +++++++++++++++++++++++++++++++++++-----------
1 file changed, 77 insertions(+), 24 deletions(-)

diff --git a/drivers/clk/clk-npcm7xx.c b/drivers/clk/clk-npcm7xx.c
index 740af90a9508..a5206ee88f4c 100644
--- a/drivers/clk/clk-npcm7xx.c
+++ b/drivers/clk/clk-npcm7xx.c
@@ -7,17 +7,28 @@
* Copyright (C) 2018 Nuvoton Technologies [email protected]
*/

-#include <linux/module.h>
-#include <linux/clk-provider.h>
-#include <linux/io.h>
-#include <linux/kernel.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/slab.h>
-#include <linux/err.h>
-#include <linux/bitfield.h>
-
-#include <dt-bindings/clock/nuvoton,npcm7xx-clock.h>
+
+
+
+ #include <linux/module.h>
+ #include <linux/clk.h>
+ #include <linux/clk-provider.h>
+ #include <linux/device.h>
+ #include <linux/io.h>
+ #include <linux/kernel.h>
+ #include <linux/of.h>
+ #include <linux/of_device.h>
+ #include <linux/of_platform.h>
+ #include <linux/of_address.h>
+ #include <linux/platform_device.h>
+ #include <linux/slab.h>
+ #include <linux/err.h>
+ #include <linux/rational.h>
+ #include <linux/bitfield.h>
+ #include <dt-bindings/clock/nuvoton,npcm7xx-clock.h>
+
+ #include <asm/cp15.h>
+

struct npcm7xx_clk_pll {
struct clk_hw hw;
@@ -27,6 +38,9 @@ struct npcm7xx_clk_pll {

#define to_npcm7xx_clk_pll(_hw) container_of(_hw, struct npcm7xx_clk_pll, hw)

+static struct clk_hw *npcm7xx_clk_register_pll(void __iomem *pllcon,
+ const char *name, const char *parent_name, unsigned long flags);
+
#define PLLCON_LOKI BIT(31)
#define PLLCON_LOKS BIT(30)
#define PLLCON_FBDV GENMASK(27, 16)
@@ -44,7 +58,8 @@ static unsigned long npcm7xx_clk_pll_recalc_rate(struct clk_hw *hw,
u64 ret;

if (parent_rate == 0) {
- pr_err("%s: parent rate is zero", __func__);
+ pr_err("%s: parent rate is zero. reg=%x\n", __func__,
+ (u32)(pll->pllcon));
return 0;
}

@@ -61,13 +76,12 @@ static unsigned long npcm7xx_clk_pll_recalc_rate(struct clk_hw *hw,
return ret;
}

-static const struct clk_ops npcm7xx_clk_pll_ops = {
+const struct clk_ops npcm7xx_clk_pll_ops = {
.recalc_rate = npcm7xx_clk_pll_recalc_rate,
};

-static struct clk_hw *
-npcm7xx_clk_register_pll(void __iomem *pllcon, const char *name,
- const char *parent_name, unsigned long flags)
+static struct clk_hw *npcm7xx_clk_register_pll(void __iomem *pllcon,
+ const char *name, const char *parent_name, unsigned long flags)
{
struct npcm7xx_clk_pll *pll;
struct clk_init_data init;
@@ -78,7 +92,8 @@ npcm7xx_clk_register_pll(void __iomem *pllcon, const char *name,
if (!pll)
return ERR_PTR(-ENOMEM);

- pr_debug("%s reg, name=%s, p=%s\n", __func__, name, parent_name);
+ pr_debug("%s reg, reg=0x%x, name=%s, p=%s\n",
+ __func__, (unsigned int)pllcon, name, parent_name);

init.name = name;
init.ops = &npcm7xx_clk_pll_ops;
@@ -544,9 +559,11 @@ static void __init npcm7xx_clk_init(struct device_node *clk_np)
void __iomem *clk_base;
struct resource res;
struct clk_hw *hw;
+ struct clk *clk;
int ret;
int i;

+ clk_base = NULL;
ret = of_address_to_resource(clk_np, 0, &res);
if (ret) {
pr_err("%s: failed to get resource, ret %d\n", clk_np->name,
@@ -560,14 +577,44 @@ static void __init npcm7xx_clk_init(struct device_node *clk_np)

npcm7xx_clk_data = kzalloc(sizeof(*npcm7xx_clk_data->hws) *
NPCM7XX_NUM_CLOCKS + sizeof(npcm7xx_clk_data), GFP_KERNEL);
- if (!npcm7xx_clk_data)
+
+ npcm7xx_clk_data->num = 0;
+
+ if (!npcm7xx_clk_data->hws) {
+ pr_err("Can't alloc npcm7xx_clk_data\n");
goto npcm7xx_init_np_err;
+ }

npcm7xx_clk_data->num = NPCM7XX_NUM_CLOCKS;

for (i = 0; i < NPCM7XX_NUM_CLOCKS; i++)
npcm7xx_clk_data->hws[i] = ERR_PTR(-EPROBE_DEFER);

+ /* Read fixed clocks. These 3 clocks must be defined in DT */
+ clk = of_clk_get_by_name(clk_np, NPCM7XX_CLK_S_REFCLK);
+ if (IS_ERR(clk)) {
+ pr_err("failed to find external REFCLK on device tree, err=%ld\n",
+ PTR_ERR(clk));
+ clk_put(clk);
+ goto npcm7xx_init_fail_no_clk_on_dt;
+ }
+
+ clk = of_clk_get_by_name(clk_np, NPCM7XX_CLK_S_SYSBYPCK);
+ if (IS_ERR(clk)) {
+ pr_err("failed to find external SYSBYPCK on device tree, err=%ld\n",
+ PTR_ERR(clk));
+ clk_put(clk);
+ goto npcm7xx_init_fail_no_clk_on_dt;
+ }
+
+ clk = of_clk_get_by_name(clk_np, NPCM7XX_CLK_S_MCBYPCK);
+ if (IS_ERR(clk)) {
+ pr_err("failed to find external MCBYPCK on device tree, err=%ld\n",
+ PTR_ERR(clk));
+ clk_put(clk);
+ goto npcm7xx_init_fail_no_clk_on_dt;
+ }
+
/* Register plls */
for (i = 0; i < ARRAY_SIZE(npcm7xx_plls); i++) {
const struct npcm7xx_clk_pll_data *pll_data = &npcm7xx_plls[i];
@@ -584,16 +631,16 @@ static void __init npcm7xx_clk_init(struct device_node *clk_np)
}

/* Register fixed dividers */
- hw = clk_hw_register_fixed_factor(NULL, NPCM7XX_CLK_S_PLL1_DIV2,
+ clk = clk_register_fixed_factor(NULL, NPCM7XX_CLK_S_PLL1_DIV2,
NPCM7XX_CLK_S_PLL1, 0, 1, 2);
- if (IS_ERR(hw)) {
+ if (IS_ERR(clk)) {
pr_err("npcm7xx_clk: Can't register fixed div\n");
goto npcm7xx_init_fail;
}

- hw = clk_hw_register_fixed_factor(NULL, NPCM7XX_CLK_S_PLL2_DIV2,
+ clk = clk_register_fixed_factor(NULL, NPCM7XX_CLK_S_PLL2_DIV2,
NPCM7XX_CLK_S_PLL2, 0, 1, 2);
- if (IS_ERR(hw)) {
+ if (IS_ERR(clk)) {
pr_err("npcm7xx_clk: Can't register div2\n");
goto npcm7xx_init_fail;
}
@@ -646,11 +693,17 @@ static void __init npcm7xx_clk_init(struct device_node *clk_np)

return;

+npcm7xx_init_fail_no_clk_on_dt:
+ pr_err("see Documentation/devicetree/bindings/clock/");
+ pr_err("nuvoton,npcm750-clk.txt for details\n");
npcm7xx_init_fail:
- kfree(npcm7xx_clk_data->hws);
+ if (npcm7xx_clk_data->num)
+ kfree(npcm7xx_clk_data->hws);
npcm7xx_init_np_err:
- iounmap(clk_base);
+ if (clk_base != NULL)
+ iounmap(clk_base);
npcm7xx_init_error:
of_node_put(clk_np);
+ pr_err("clk setup fail\n");
}
CLK_OF_DECLARE(npcm7xx_clk_init, "nuvoton,npcm750-clk", npcm7xx_clk_init);
--
2.14.1