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>

7 files changed, 43 insertions, 85 deletions

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 832f71dcd8c4..7ff869007ba4 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -319,9 +319,10 @@ int pinctrl_get_group_selector(struct pinctrl_dev *pctldev,
                                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 @@ static int pinctrl_groups_show(struct seq_file *s, void *what)
 {
         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 @@ static int pinctrl_check_ops(struct pinctrl_dev *pctldev)
         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 7321e8601294..eb3a14f4b866 100644
--- a/drivers/pinctrl/pinconf.c
+++ b/drivers/pinctrl/pinconf.c
@@ -495,6 +495,7 @@ static int pinconf_groups_show(struct seq_file *s, void *what)
         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 @@ static int pinconf_groups_show(struct seq_file *s, void *what)
 
         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 079dce0e93e9..7644e42ac211 100644
--- a/drivers/pinctrl/pinctrl-pxa3xx.c
+++ b/drivers/pinctrl/pinctrl-pxa3xx.c
@@ -25,20 +25,18 @@ static struct pinctrl_gpio_range pxa3xx_pinctrl_gpio_range = {
         .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 @@ static int pxa3xx_get_group_pins(struct pinctrl_dev *pctrldev,
                                  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 int pxa3xx_pmx_request_gpio(struct pinctrl_dev *pctrldev,
 }
 
 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 6b3534cc051a..ba15b1a29e52 100644
--- a/drivers/pinctrl/pinctrl-sirf.c
+++ b/drivers/pinctrl/pinctrl-sirf.c
@@ -853,18 +853,14 @@ static const struct sirfsoc_pin_group sirfsoc_pin_groups[] = {
         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 @@ static int sirfsoc_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector
                                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 void sirfsoc_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s
 }
 
 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 @@ static void sirfsoc_pinmux_disable(struct pinctrl_dev *pmxdev, unsigned selector
         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 int sirfsoc_pinmux_request_gpio(struct pinctrl_dev *pmxdev,
 }
 
 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 9b329688120c..41311a2a4256 100644
--- a/drivers/pinctrl/pinctrl-tegra.c
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -53,15 +53,11 @@ static inline void pmx_writel(struct tegra_pmx *pmx, u32 val, u32 bank, u32 reg)
         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 @@ static const char *tegra_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
 {
         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 @@ static int tegra_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
 {
         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 void tegra_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
 }
 
 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 @@ static const char *tegra_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
 {
         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 @@ static int tegra_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
 {
         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 @@ static int tegra_pinctrl_enable(struct pinctrl_dev *pctldev, unsigned function,
         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 @@ static void tegra_pinctrl_disable(struct pinctrl_dev *pctldev,
         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 void tegra_pinctrl_disable(struct pinctrl_dev *pctldev,
 }
 
 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 @@ static int tegra_pinconf_group_get(struct pinctrl_dev *pctldev,
         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 @@ static int tegra_pinconf_group_set(struct pinctrl_dev *pctldev,
         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 26eb8ccd72d5..05d029911be6 100644
--- a/drivers/pinctrl/pinctrl-u300.c
+++ b/drivers/pinctrl/pinctrl-u300.c
@@ -836,18 +836,14 @@ static const struct u300_pin_group u300_pin_groups[] = {
         },
 };
 
-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 @@ static int u300_get_group_pins(struct pinctrl_dev *pctldev, unsigned selector,
                                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 void u300_pin_dbg_show(struct pinctrl_dev *pctldev, struct seq_file *s,
 }
 
 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 @@ static void u300_pmx_disable(struct pinctrl_dev *pctldev, unsigned selector,
         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 int u300_pmx_get_groups(struct pinctrl_dev *pctldev, unsigned selector,
 }
 
 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 4e62783a573a..375b214780e9 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 @@ int pinmux_check_ops(struct pinctrl_dev *pctldev)
                 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 @@ static int pinmux_func_name_to_selector(struct pinctrl_dev *pctldev,
                                         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 @@ static int pinmux_functions_show(struct seq_file *s, void *what)
 {
         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;