[PATCH 5.17 1/2] pinctrl: thunderbay: comment process of building functions a bit

[PATCH 5.17 1/2] pinctrl: thunderbay: comment process of building functions a bit

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

This should make code a bit easier to follow. While at it use some "for"
loops to simplify array iteration loops.

Ref: 5d0674999cc5 ("pinctrl: keembay: comment process of building functions a bit")
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 drivers/pinctrl/pinctrl-thunderbay.c | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-thunderbay.c b/drivers/pinctrl/pinctrl-thunderbay.c
index b5b47f4dd774..4756a23ca572 100644
--- a/drivers/pinctrl/pinctrl-thunderbay.c
+++ b/drivers/pinctrl/pinctrl-thunderbay.c
@@ -839,27 +839,30 @@ static int thunderbay_build_functions(struct thunderbay_pinctrl *tpc)
 	void *ptr;
 	int pin;
 
-	/* Total number of functions is unknown at this point. Allocate first. */
+	/*
+	 * Allocate maximum possible number of functions. Assume every pin
+	 * being part of 8 (hw maximum) globally unique muxes.
+	 */
 	tpc->nfuncs = 0;
 	thunderbay_funcs = kcalloc(tpc->soc->npins * 8,
 				   sizeof(*thunderbay_funcs), GFP_KERNEL);
 	if (!thunderbay_funcs)
 		return -ENOMEM;
 
-	/* Find total number of functions and each's properties */
+	/* Setup 1 function for each unique mux */
 	for (pin = 0; pin < tpc->soc->npins; pin++) {
 		const struct pinctrl_pin_desc *pin_info = thunderbay_pins + pin;
-		struct thunderbay_mux_desc *pin_mux = pin_info->drv_data;
+		struct thunderbay_mux_desc *pin_mux;
 
-		while (pin_mux->name) {
-			struct function_desc *func = thunderbay_funcs;
+		for (pin_mux = pin_info->drv_data; pin_mux->name; pin_mux++) {
+			struct function_desc *func;
 
-			while (func->name) {
+			/* Check if we already have function for this mux */
+			for (func = thunderbay_funcs; func->name; func++) {
 				if (!strcmp(pin_mux->name, func->name)) {
 					func->num_group_names++;
 					break;
 				}
-				func++;
 			}
 
 			if (!func->name) {
@@ -868,8 +871,6 @@ static int thunderbay_build_functions(struct thunderbay_pinctrl *tpc)
 				func->data = (int *)&pin_mux->mode;
 				tpc->nfuncs++;
 			}
-
-			pin_mux++;
 		}
 	}
 
-- 
2.31.1

[PATCH 5.17 2/2] pinctrl: thunderbay: rework loops looking for groups names

[Rafał Miłecki]

From: Rafał Miłecki <rafal@milecki.pl>

Make the outer loop iterate over functions as that's the real subject.
This simplifies code (and reduces amount of lines of code) as allocating
memory for names doesn't require extra checks anymore.

While at it use local "group_names" variable. It fixes:
drivers/pinctrl/pinctrl-thunderbay.c: In function 'thunderbay_add_functions':
drivers/pinctrl/pinctrl-thunderbay.c:815:8: warning: assignment discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
  815 |    grp = func->group_names;
      |        ^

Ref: c26c4bfc1040 ("pinctrl: keembay: rework loops looking for groups names")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
 drivers/pinctrl/pinctrl-thunderbay.c | 71 ++++++++++------------------
 1 file changed, 25 insertions(+), 46 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-thunderbay.c b/drivers/pinctrl/pinctrl-thunderbay.c
index 4756a23ca572..79d44bca039e 100644
--- a/drivers/pinctrl/pinctrl-thunderbay.c
+++ b/drivers/pinctrl/pinctrl-thunderbay.c
@@ -773,63 +773,42 @@ static int thunderbay_build_groups(struct thunderbay_pinctrl *tpc)
 
 static int thunderbay_add_functions(struct thunderbay_pinctrl *tpc, struct function_desc *funcs)
 {
-	struct function_desc *function = funcs;
 	int i;
 
 	/* Assign the groups for each function */
-	for (i = 0; i < tpc->soc->npins; i++) {
-		const struct pinctrl_pin_desc *pin_info = thunderbay_pins + i;
-		struct thunderbay_mux_desc *pin_mux = pin_info->drv_data;
-
-		while (pin_mux->name) {
-			const char **grp;
-			int j, grp_num, match = 0;
-			size_t grp_size;
-			struct function_desc *func;
-
-			for (j = 0; j < tpc->nfuncs; j++) {
-				if (!strcmp(pin_mux->name, function[j].name)) {
-					match = 1;
-					break;
-				}
-			}
-
-			if (!match)
-				return -EINVAL;
-
-			func = function + j;
-			grp_num = func->num_group_names;
-			grp_size = sizeof(*func->group_names);
-
-			if (!func->group_names) {
-				func->group_names = devm_kcalloc(tpc->dev,
-								 grp_num,
-								 grp_size,
-								 GFP_KERNEL);
-				if (!func->group_names) {
-					kfree(func);
-					return -ENOMEM;
-				}
+	for (i = 0; i < tpc->nfuncs; i++) {
+		struct function_desc *func = &funcs[i];
+		const char **group_names;
+		unsigned int grp_idx = 0;
+		int j;
+
+		group_names = devm_kcalloc(tpc->dev, func->num_group_names,
+					   sizeof(*group_names), GFP_KERNEL);
+		if (!group_names)
+			return -ENOMEM;
+
+		for (j = 0; j < tpc->soc->npins; j++) {
+			const struct pinctrl_pin_desc *pin_info = &thunderbay_pins[j];
+			struct thunderbay_mux_desc *pin_mux;
+
+			for (pin_mux = pin_info->drv_data; pin_mux->name; pin_mux++) {
+				if (!strcmp(pin_mux->name, func->name))
+					group_names[grp_idx++] = pin_info->name;
 			}
-
-			grp = func->group_names;
-			while (*grp)
-				grp++;
-
-			*grp = pin_info->name;
-			pin_mux++;
 		}
+
+		func->group_names = group_names;
 	}
 
 	/* Add all functions */
 	for (i = 0; i < tpc->nfuncs; i++) {
 		pinmux_generic_add_function(tpc->pctrl,
-					    function[i].name,
-					    function[i].group_names,
-					    function[i].num_group_names,
-					    function[i].data);
+					    funcs[i].name,
+					    funcs[i].group_names,
+					    funcs[i].num_group_names,
+					    funcs[i].data);
 	}
-	kfree(function);
+	kfree(funcs);
 	return 0;
 }
 
-- 
2.31.1

Re: [PATCH 5.17 1/2] pinctrl: thunderbay: comment process of building functions a bit

[Linus Walleij]

On Tue, Jan 11, 2022 at 6:29 PM Rafał Miłecki <zajec5@gmail.com> wrote:

> From: Rafał Miłecki <rafal@milecki.pl>
>
> This should make code a bit easier to follow. While at it use some "for"
> loops to simplify array iteration loops.
>
> Ref: 5d0674999cc5 ("pinctrl: keembay: comment process of building functions a bit")
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

Patches applied!

Yours,
Linus Walleij