pinctrl: replace list_*() with get_*_count()

Most of the SoC drivers implement list_groups() and list_functions()
routines for pinctrl and pinmux. These routines continue returning
zero until the selector argument is greater than total count of
available groups or functions.

This patch replaces these list_*() routines with get_*_count()
routines, which returns the number of available selection for SoC
driver. pinctrl layer will use this value to check the range it can
choose.

This patch fixes all user drivers for this change. There are other
routines in user drivers, which have checks to check validity of
selector passed to them. It is also no more required and hence
removed.

Documentation updated as well.

Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
[Folded in fix and fixed a minor merge artifact manually]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 832f71d..7ff8690 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -319,9 +319,10 @@
 			       const char *pin_group)
 {
 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
+	unsigned ngroups = pctlops->get_groups_count(pctldev);
 	unsigned group_selector = 0;
 
-	while (pctlops->list_groups(pctldev, group_selector) >= 0) {
+	while (group_selector < ngroups) {
 		const char *gname = pctlops->get_group_name(pctldev,
 							    group_selector);
 		if (!strcmp(gname, pin_group)) {
@@ -941,12 +942,13 @@
 {
 	struct pinctrl_dev *pctldev = s->private;
 	const struct pinctrl_ops *ops = pctldev->desc->pctlops;
-	unsigned selector = 0;
+	unsigned ngroups, selector = 0;
 
+	ngroups = ops->get_groups_count(pctldev);
 	mutex_lock(&pinctrl_mutex);
 
 	seq_puts(s, "registered pin groups:\n");
-	while (ops->list_groups(pctldev, selector) >= 0) {
+	while (selector < ngroups) {
 		const unsigned *pins;
 		unsigned num_pins;
 		const char *gname = ops->get_group_name(pctldev, selector);
@@ -1261,7 +1263,7 @@
 	const struct pinctrl_ops *ops = pctldev->desc->pctlops;
 
 	if (!ops ||
-	    !ops->list_groups ||
+	    !ops->get_groups_count ||
 	    !ops->get_group_name ||
 	    !ops->get_group_pins)
 		return -EINVAL;
diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c
index 7321e86..eb3a14f 100644
--- a/drivers/pinctrl/pinconf.c
+++ b/drivers/pinctrl/pinconf.c
@@ -495,6 +495,7 @@
 	struct pinctrl_dev *pctldev = s->private;
 	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
 	const struct pinconf_ops *ops = pctldev->desc->confops;
+	unsigned ngroups = pctlops->get_groups_count(pctldev);
 	unsigned selector = 0;
 
 	if (!ops || !ops->pin_config_group_get)
@@ -505,7 +506,7 @@
 
 	mutex_lock(&pinctrl_mutex);
 
-	while (pctlops->list_groups(pctldev, selector) >= 0) {
+	while (selector < ngroups) {
 		const char *gname = pctlops->get_group_name(pctldev, selector);
 
 		seq_printf(s, "%u (%s):", selector, gname);
diff --git a/drivers/pinctrl/pinctrl-pxa3xx.c b/drivers/pinctrl/pinctrl-pxa3xx.c
index 079dce0..7644e42 100644
--- a/drivers/pinctrl/pinctrl-pxa3xx.c
+++ b/drivers/pinctrl/pinctrl-pxa3xx.c
@@ -25,20 +25,18 @@
 	.pin_base	= 0,
 };
 
-static int pxa3xx_list_groups(struct pinctrl_dev *pctrldev, unsigned selector)
+static int pxa3xx_get_groups_count(struct pinctrl_dev *pctrldev)
 {
 	struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
-	if (selector >= info->num_grps)
-		return -EINVAL;
-	return 0;
+
+	return info->num_grps;
 }
 
 static const char *pxa3xx_get_group_name(struct pinctrl_dev *pctrldev,
 					 unsigned selector)
 {
 	struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
-	if (selector >= info->num_grps)
-		return NULL;
+
 	return info->grps[selector].name;
 }
 
@@ -48,25 +46,23 @@
 				 unsigned *num_pins)
 {
 	struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
-	if (selector >= info->num_grps)
-		return -EINVAL;
+
 	*pins = info->grps[selector].pins;
 	*num_pins = info->grps[selector].npins;
 	return 0;
 }
 
 static struct pinctrl_ops pxa3xx_pctrl_ops = {
-	.list_groups	= pxa3xx_list_groups,
+	.get_groups_count = pxa3xx_get_groups_count,
 	.get_group_name	= pxa3xx_get_group_name,
 	.get_group_pins	= pxa3xx_get_group_pins,
 };
 
-static int pxa3xx_pmx_list_func(struct pinctrl_dev *pctrldev, unsigned func)
+static int pxa3xx_pmx_get_funcs_count(struct pinctrl_dev *pctrldev)
 {
 	struct pxa3xx_pinmux_info *info = pinctrl_dev_get_drvdata(pctrldev);
-	if (func >= info->num_funcs)
-		return -EINVAL;
-	return 0;
+
+	return info->num_funcs;
 }
 
 static const char *pxa3xx_pmx_get_func_name(struct pinctrl_dev *pctrldev,
@@ -170,7 +166,7 @@
 }
 
 static struct pinmux_ops pxa3xx_pmx_ops = {
-	.list_functions		= pxa3xx_pmx_list_func,
+	.get_functions_count	= pxa3xx_pmx_get_funcs_count,
 	.get_function_name	= pxa3xx_pmx_get_func_name,
 	.get_function_groups	= pxa3xx_pmx_get_groups,
 	.enable			= pxa3xx_pmx_enable,
diff --git a/drivers/pinctrl/pinctrl-sirf.c b/drivers/pinctrl/pinctrl-sirf.c
index 6b3534c..ba15b1a 100644
--- a/drivers/pinctrl/pinctrl-sirf.c
+++ b/drivers/pinctrl/pinctrl-sirf.c
@@ -853,18 +853,14 @@
 	SIRFSOC_PIN_GROUP("gpsgrp", gps_pins),
 };
 
-static int sirfsoc_list_groups(struct pinctrl_dev *pctldev, unsigned selector)
+static int sirfsoc_get_groups_count(struct pinctrl_dev *pctldev)
 {
-	if (selector >= ARRAY_SIZE(sirfsoc_pin_groups))
-		return -EINVAL;
-	return 0;
+	return ARRAY_SIZE(sirfsoc_pin_groups);
 }
 
 static const char *sirfsoc_get_group_name(struct pinctrl_dev *pctldev,
 				       unsigned selector)
 {
-	if (selector >= ARRAY_SIZE(sirfsoc_pin_groups))
-		return NULL;
 	return sirfsoc_pin_groups[selector].name;
 }
 
@@ -872,8 +868,6 @@
 			       const unsigned **pins,
 			       unsigned *num_pins)
 {
-	if (selector >= ARRAY_SIZE(sirfsoc_pin_groups))
-		return -EINVAL;
 	*pins = sirfsoc_pin_groups[selector].pins;
 	*num_pins = sirfsoc_pin_groups[selector].num_pins;
 	return 0;
@@ -886,7 +880,7 @@
 }
 
 static struct pinctrl_ops sirfsoc_pctrl_ops = {
-	.list_groups = sirfsoc_list_groups,
+	.get_groups_count = sirfsoc_get_groups_count,
 	.get_group_name = sirfsoc_get_group_name,
 	.get_group_pins = sirfsoc_get_group_pins,
 	.pin_dbg_show = sirfsoc_pin_dbg_show,
@@ -1033,11 +1027,9 @@
 	sirfsoc_pinmux_endisable(spmx, selector, false);
 }
 
-static int sirfsoc_pinmux_list_funcs(struct pinctrl_dev *pmxdev, unsigned selector)
+static int sirfsoc_pinmux_get_funcs_count(struct pinctrl_dev *pmxdev)
 {
-	if (selector >= ARRAY_SIZE(sirfsoc_pmx_functions))
-		return -EINVAL;
-	return 0;
+	return ARRAY_SIZE(sirfsoc_pmx_functions);
 }
 
 static const char *sirfsoc_pinmux_get_func_name(struct pinctrl_dev *pctldev,
@@ -1074,9 +1066,9 @@
 }
 
 static struct pinmux_ops sirfsoc_pinmux_ops = {
-	.list_functions = sirfsoc_pinmux_list_funcs,
 	.enable = sirfsoc_pinmux_enable,
 	.disable = sirfsoc_pinmux_disable,
+	.get_functions_count = sirfsoc_pinmux_get_funcs_count,
 	.get_function_name = sirfsoc_pinmux_get_func_name,
 	.get_function_groups = sirfsoc_pinmux_get_groups,
 	.gpio_request_enable = sirfsoc_pinmux_request_gpio,
diff --git a/drivers/pinctrl/pinctrl-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
index 9b32968..41311a2 100644
--- a/drivers/pinctrl/pinctrl-tegra.c
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -53,15 +53,11 @@
 	writel(val, pmx->regs[bank] + reg);
 }
 
-static int tegra_pinctrl_list_groups(struct pinctrl_dev *pctldev,
-				     unsigned group)
+static int tegra_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (group >= pmx->soc->ngroups)
-		return -EINVAL;
-
-	return 0;
+	return pmx->soc->ngroups;
 }
 
 static const char *tegra_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
@@ -69,9 +65,6 @@
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (group >= pmx->soc->ngroups)
-		return NULL;
-
 	return pmx->soc->groups[group].name;
 }
 
@@ -82,9 +75,6 @@
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (group >= pmx->soc->ngroups)
-		return -EINVAL;
-
 	*pins = pmx->soc->groups[group].pins;
 	*num_pins = pmx->soc->groups[group].npins;
 
@@ -99,21 +89,17 @@
 }
 
 static struct pinctrl_ops tegra_pinctrl_ops = {
-	.list_groups = tegra_pinctrl_list_groups,
+	.get_groups_count = tegra_pinctrl_get_groups_count,
 	.get_group_name = tegra_pinctrl_get_group_name,
 	.get_group_pins = tegra_pinctrl_get_group_pins,
 	.pin_dbg_show = tegra_pinctrl_pin_dbg_show,
 };
 
-static int tegra_pinctrl_list_funcs(struct pinctrl_dev *pctldev,
-				    unsigned function)
+static int tegra_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (function >= pmx->soc->nfunctions)
-		return -EINVAL;
-
-	return 0;
+	return pmx->soc->nfunctions;
 }
 
 static const char *tegra_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
@@ -121,9 +107,6 @@
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (function >= pmx->soc->nfunctions)
-		return NULL;
-
 	return pmx->soc->functions[function].name;
 }
 
@@ -134,9 +117,6 @@
 {
 	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
 
-	if (function >= pmx->soc->nfunctions)
-		return -EINVAL;
-
 	*groups = pmx->soc->functions[function].groups;
 	*num_groups = pmx->soc->functions[function].ngroups;
 
@@ -151,8 +131,6 @@
 	int i;
 	u32 val;
 
-	if (group >= pmx->soc->ngroups)
-		return -EINVAL;
 	g = &pmx->soc->groups[group];
 
 	if (g->mux_reg < 0)
@@ -180,8 +158,6 @@
 	const struct tegra_pingroup *g;
 	u32 val;
 
-	if (group >= pmx->soc->ngroups)
-		return;
 	g = &pmx->soc->groups[group];
 
 	if (g->mux_reg < 0)
@@ -194,7 +170,7 @@
 }
 
 static struct pinmux_ops tegra_pinmux_ops = {
-	.list_functions = tegra_pinctrl_list_funcs,
+	.get_functions_count = tegra_pinctrl_get_funcs_count,
 	.get_function_name = tegra_pinctrl_get_func_name,
 	.get_function_groups = tegra_pinctrl_get_func_groups,
 	.enable = tegra_pinctrl_enable,
@@ -324,8 +300,6 @@
 	s16 reg;
 	u32 val, mask;
 
-	if (group >= pmx->soc->ngroups)
-		return -EINVAL;
 	g = &pmx->soc->groups[group];
 
 	ret = tegra_pinconf_reg(pmx, g, param, &bank, &reg, &bit, &width);
@@ -353,8 +327,6 @@
 	s16 reg;
 	u32 val, mask;
 
-	if (group >= pmx->soc->ngroups)
-		return -EINVAL;
 	g = &pmx->soc->groups[group];
 
 	ret = tegra_pinconf_reg(pmx, g, param, &bank, &reg, &bit, &width);
diff --git a/drivers/pinctrl/pinctrl-u300.c b/drivers/pinctrl/pinctrl-u300.c
index 26eb8cc..05d0299 100644
--- a/drivers/pinctrl/pinctrl-u300.c
+++ b/drivers/pinctrl/pinctrl-u300.c
@@ -836,18 +836,14 @@
 	},
 };
 
-static int u300_list_groups(struct pinctrl_dev *pctldev, unsigned selector)
+static int u300_get_groups_count(struct pinctrl_dev *pctldev)
 {
-	if (selector >= ARRAY_SIZE(u300_pin_groups))
-		return -EINVAL;
-	return 0;
+	return ARRAY_SIZE(u300_pin_groups);
 }
 
 static const char *u300_get_group_name(struct pinctrl_dev *pctldev,
 				       unsigned selector)
 {
-	if (selector >= ARRAY_SIZE(u300_pin_groups))
-		return NULL;
 	return u300_pin_groups[selector].name;
 }
 
@@ -855,8 +851,6 @@
 			       const unsigned **pins,
 			       unsigned *num_pins)
 {
-	if (selector >= ARRAY_SIZE(u300_pin_groups))
-		return -EINVAL;
 	*pins = u300_pin_groups[selector].pins;
 	*num_pins = u300_pin_groups[selector].num_pins;
 	return 0;
@@ -869,7 +863,7 @@
 }
 
 static struct pinctrl_ops u300_pctrl_ops = {
-	.list_groups = u300_list_groups,
+	.get_groups_count = u300_get_groups_count,
 	.get_group_name = u300_get_group_name,
 	.get_group_pins = u300_get_group_pins,
 	.pin_dbg_show = u300_pin_dbg_show,
@@ -991,11 +985,9 @@
 	u300_pmx_endisable(upmx, selector, false);
 }
 
-static int u300_pmx_list_funcs(struct pinctrl_dev *pctldev, unsigned selector)
+static int u300_pmx_get_funcs_count(struct pinctrl_dev *pctldev)
 {
-	if (selector >= ARRAY_SIZE(u300_pmx_functions))
-		return -EINVAL;
-	return 0;
+	return ARRAY_SIZE(u300_pmx_functions);
 }
 
 static const char *u300_pmx_get_func_name(struct pinctrl_dev *pctldev,
@@ -1014,7 +1006,7 @@
 }
 
 static struct pinmux_ops u300_pmx_ops = {
-	.list_functions = u300_pmx_list_funcs,
+	.get_functions_count = u300_pmx_get_funcs_count,
 	.get_function_name = u300_pmx_get_func_name,
 	.get_function_groups = u300_pmx_get_groups,
 	.enable = u300_pmx_enable,
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 4e62783..375b214 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -33,10 +33,11 @@
 int pinmux_check_ops(struct pinctrl_dev *pctldev)
 {
 	const struct pinmux_ops *ops = pctldev->desc->pmxops;
+	unsigned nfuncs = ops->get_functions_count(pctldev);
 	unsigned selector = 0;
 
 	/* Check that we implement required operations */
-	if (!ops->list_functions ||
+	if (!ops->get_functions_count ||
 	    !ops->get_function_name ||
 	    !ops->get_function_groups ||
 	    !ops->enable ||
@@ -44,7 +45,7 @@
 		return -EINVAL;
 
 	/* Check that all functions registered have names */
-	while (ops->list_functions(pctldev, selector) >= 0) {
+	while (selector < nfuncs) {
 		const char *fname = ops->get_function_name(pctldev,
 							   selector);
 		if (!fname) {
@@ -287,10 +288,11 @@
 					const char *function)
 {
 	const struct pinmux_ops *ops = pctldev->desc->pmxops;
+	unsigned nfuncs = ops->get_functions_count(pctldev);
 	unsigned selector = 0;
 
 	/* See if this pctldev has this function */
-	while (ops->list_functions(pctldev, selector) >= 0) {
+	while (selector < nfuncs) {
 		const char *fname = ops->get_function_name(pctldev,
 							   selector);
 
@@ -477,11 +479,12 @@
 {
 	struct pinctrl_dev *pctldev = s->private;
 	const struct pinmux_ops *pmxops = pctldev->desc->pmxops;
+	unsigned nfuncs = pmxops->get_functions_count(pctldev);
 	unsigned func_selector = 0;
 
 	mutex_lock(&pinctrl_mutex);
 
-	while (pmxops->list_functions(pctldev, func_selector) >= 0) {
+	while (func_selector < nfuncs) {
 		const char *func = pmxops->get_function_name(pctldev,
 							  func_selector);
 		const char * const *groups;