| Message ID | 20200608125143.GA2789203@x1 (mailing list archive) |
|---|---|
| State | Mainlined |
| Commit | f46fe79ff1b65692a65266a5bec6dbe2bf7fc70f |
| Headers | show |
| Series | [v2] pinctrl-single: fix pcs_parse_pinconf() return value | expand |
* Drew Fustini <drew@beagleboard.org> [200608 12:52]: > This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no > pinctrl_map is added. The current behavior is to return 0 when > !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() > incorrectly assumes that a map was added and sets num_maps = 2. ... > Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") It would be good to get an ack/tested-by from Haojian for this. The patch looks right to me: Acked-by: Tony Lindgren <tony@atomide.com>
On Mon, Jun 8, 2020 at 2:51 PM Drew Fustini <drew@beagleboard.org> wrote: > This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no > pinctrl_map is added. The current behavior is to return 0 when > !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() > incorrectly assumes that a map was added and sets num_maps = 2. > > Analysis: > ========= > The function pcs_parse_one_pinctrl_entry() calls pcs_parse_pinconf() > if PCS_HAS_PINCONF is enabled. The function pcs_parse_pinconf() > returns 0 to indicate there was no error and num_maps is then set to 2: > > 980 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, > 981 struct device_node *np, > 982 struct pinctrl_map **map, > 983 unsigned *num_maps, > 984 const char **pgnames) > 985 { > <snip> > 1053 (*map)->type = PIN_MAP_TYPE_MUX_GROUP; > 1054 (*map)->data.mux.group = np->name; > 1055 (*map)->data.mux.function = np->name; > 1056 > 1057 if (PCS_HAS_PINCONF && function) { > 1058 res = pcs_parse_pinconf(pcs, np, function, map); > 1059 if (res) > 1060 goto free_pingroups; > 1061 *num_maps = 2; > 1062 } else { > 1063 *num_maps = 1; > 1064 } > > However, pcs_parse_pinconf() will also return 0 if !PCS_HAS_PINCONF or > !nconfs. I believe these conditions should indicate that no map was > added by returning -ENOTSUPP. Otherwise pcs_parse_one_pinctrl_entry() > will set num_maps = 2 even though no maps were successfully added, as > it does not reach "m++" on line 940: > > 895 static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > 896 struct pcs_function *func, > 897 struct pinctrl_map **map) > 898 > 899 { > 900 struct pinctrl_map *m = *map; > <snip> > 917 /* If pinconf isn't supported, don't parse properties in below. */ > 918 if (!PCS_HAS_PINCONF) > 919 return 0; > 920 > 921 /* cacluate how much properties are supported in current node */ > 922 for (i = 0; i < ARRAY_SIZE(prop2); i++) { > 923 if (of_find_property(np, prop2[i].name, NULL)) > 924 nconfs++; > 925 } > 926 for (i = 0; i < ARRAY_SIZE(prop4); i++) { > 927 if (of_find_property(np, prop4[i].name, NULL)) > 928 nconfs++; > 929 } > 930 if (!nconfs) > 919 return 0; > 932 > 933 func->conf = devm_kcalloc(pcs->dev, > 934 nconfs, sizeof(struct pcs_conf_vals), > 935 GFP_KERNEL); > 936 if (!func->conf) > 937 return -ENOMEM; > 938 func->nconfs = nconfs; > 939 conf = &(func->conf[0]); > 940 m++; > > This situtation will cause a boot failure [0] on the BeagleBone Black > (AM3358) when am33xx_pinmux node in arch/arm/boot/dts/am33xx-l4.dtsi > has compatible = "pinconf-single" instead of "pinctrl-single". > > The patch fixes this issue by returning -ENOSUPP when !PCS_HAS_PINCONF > or !nconfs, so that pcs_parse_one_pinctrl_entry() will know that no > map was added. > > Logic is also added to pcs_parse_one_pinctrl_entry() to distinguish > between -ENOSUPP and other errors. In the case of -ENOSUPP, num_maps > is set to 1 as it is valid for pinconf to be enabled and a given pin > group to not any pinconf properties. > > [0] https://lore.kernel.org/linux-omap/20200529175544.GA3766151@x1/ > > Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") > Signed-off-by: Drew Fustini <drew@beagleboard.org> Patch applied as non-critical (for-next) fix. If there is no hurry let's merge it this way with lots of testing along the way. Yours, Linus Walleij
On Tue, Jun 16, 2020 at 10:31:54AM +0200, Linus Walleij wrote: > On Mon, Jun 8, 2020 at 2:51 PM Drew Fustini <drew@beagleboard.org> wrote: > > > This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no > > pinctrl_map is added. The current behavior is to return 0 when > > !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() > > incorrectly assumes that a map was added and sets num_maps = 2. > > > > Analysis: > > ========= > > The function pcs_parse_one_pinctrl_entry() calls pcs_parse_pinconf() > > if PCS_HAS_PINCONF is enabled. The function pcs_parse_pinconf() > > returns 0 to indicate there was no error and num_maps is then set to 2: > > > > 980 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, > > 981 struct device_node *np, > > 982 struct pinctrl_map **map, > > 983 unsigned *num_maps, > > 984 const char **pgnames) > > 985 { > > <snip> > > 1053 (*map)->type = PIN_MAP_TYPE_MUX_GROUP; > > 1054 (*map)->data.mux.group = np->name; > > 1055 (*map)->data.mux.function = np->name; > > 1056 > > 1057 if (PCS_HAS_PINCONF && function) { > > 1058 res = pcs_parse_pinconf(pcs, np, function, map); > > 1059 if (res) > > 1060 goto free_pingroups; > > 1061 *num_maps = 2; > > 1062 } else { > > 1063 *num_maps = 1; > > 1064 } > > > > However, pcs_parse_pinconf() will also return 0 if !PCS_HAS_PINCONF or > > !nconfs. I believe these conditions should indicate that no map was > > added by returning -ENOTSUPP. Otherwise pcs_parse_one_pinctrl_entry() > > will set num_maps = 2 even though no maps were successfully added, as > > it does not reach "m++" on line 940: > > > > 895 static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > > 896 struct pcs_function *func, > > 897 struct pinctrl_map **map) > > 898 > > 899 { > > 900 struct pinctrl_map *m = *map; > > <snip> > > 917 /* If pinconf isn't supported, don't parse properties in below. */ > > 918 if (!PCS_HAS_PINCONF) > > 919 return 0; > > 920 > > 921 /* cacluate how much properties are supported in current node */ > > 922 for (i = 0; i < ARRAY_SIZE(prop2); i++) { > > 923 if (of_find_property(np, prop2[i].name, NULL)) > > 924 nconfs++; > > 925 } > > 926 for (i = 0; i < ARRAY_SIZE(prop4); i++) { > > 927 if (of_find_property(np, prop4[i].name, NULL)) > > 928 nconfs++; > > 929 } > > 930 if (!nconfs) > > 919 return 0; > > 932 > > 933 func->conf = devm_kcalloc(pcs->dev, > > 934 nconfs, sizeof(struct pcs_conf_vals), > > 935 GFP_KERNEL); > > 936 if (!func->conf) > > 937 return -ENOMEM; > > 938 func->nconfs = nconfs; > > 939 conf = &(func->conf[0]); > > 940 m++; > > > > This situtation will cause a boot failure [0] on the BeagleBone Black > > (AM3358) when am33xx_pinmux node in arch/arm/boot/dts/am33xx-l4.dtsi > > has compatible = "pinconf-single" instead of "pinctrl-single". > > > > The patch fixes this issue by returning -ENOSUPP when !PCS_HAS_PINCONF > > or !nconfs, so that pcs_parse_one_pinctrl_entry() will know that no > > map was added. > > > > Logic is also added to pcs_parse_one_pinctrl_entry() to distinguish > > between -ENOSUPP and other errors. In the case of -ENOSUPP, num_maps > > is set to 1 as it is valid for pinconf to be enabled and a given pin > > group to not any pinconf properties. > > > > [0] https://lore.kernel.org/linux-omap/20200529175544.GA3766151@x1/ > > > > Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") > > Signed-off-by: Drew Fustini <drew@beagleboard.org> > > Patch applied as non-critical (for-next) fix. > > If there is no hurry let's merge it this way with lots of testing > along the way. > > Yours, > Linus Walleij Thanks, I agree more testing is a good idea. In particular, do you have a way to followup with Haojian Zhuang within Linaro? Haojian added the generic pinconf support back in 2013, so it would be good to get his review. Also, neither Tony or I have the Hikey hardware to test. The most important to test would be those which include a .dtsi with "pinconf-single" compatible. I do plan to add pinconf-single to the AM3358 BeagleBone (which is what I am testing on), but the current mainline users are: arch/arm/boot/dts/hi3620.dtsi |- arch/arm/boot/dts/hi3620-hi4511.dts arch/arm/boot/dts/pxa3xx.dtsi |- arch/arm/boot/dts/pxa300-raumfeld-common.dtsi |- arch/arm/boot/dts/pxa300-raumfeld-connector.dts arch/arm/boot/dts/pxa300-raumfeld-controller.dts arch/arm/boot/dts/pxa300-raumfeld-speaker-l.dts arch/arm/boot/dts/pxa300-raumfeld-speaker-m.dts arch/arm/boot/dts/pxa300-raumfeld-speaker-one.dts arch/arm/boot/dts/pxa300-raumfeld-speaker-s.dts I am cc'ing Daniel Mack and Robert Jarzmi as they are listed as maintainers for the pxa300 related dts files. Those platforms using compatible = "pinctrl-single" should not be effected by this patch: arch/arm/boot/dts/am33xx-l4.dtsi (I have changed to pinconf for test) arch/arm/boot/dts/da850.dtsi arch/arm/boot/dts/dm814x.dtsi arch/arm/boot/dts/dm816x.dtsi arch/arm/boot/dts/hi3620.dtsi arch/arm/boot/dts/keystone-k2g.dtsi arch/arm/boot/dts/keystone-k2l.dtsi arch/arm/boot/dts/omap3-gta04.dtsi Thanks, Drew
On Tue, Jun 16, 2020 at 01:59:51PM +0200, Drew Fustini wrote: > On Tue, Jun 16, 2020 at 10:31:54AM +0200, Linus Walleij wrote: > > On Mon, Jun 8, 2020 at 2:51 PM Drew Fustini <drew@beagleboard.org> wrote: > > > > > This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no > > > pinctrl_map is added. The current behavior is to return 0 when > > > !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() > > > incorrectly assumes that a map was added and sets num_maps = 2. > > > > > > Analysis: > > > ========= > > > The function pcs_parse_one_pinctrl_entry() calls pcs_parse_pinconf() > > > if PCS_HAS_PINCONF is enabled. The function pcs_parse_pinconf() > > > returns 0 to indicate there was no error and num_maps is then set to 2: > > > > > > 980 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, > > > 981 struct device_node *np, > > > 982 struct pinctrl_map **map, > > > 983 unsigned *num_maps, > > > 984 const char **pgnames) > > > 985 { > > > <snip> > > > 1053 (*map)->type = PIN_MAP_TYPE_MUX_GROUP; > > > 1054 (*map)->data.mux.group = np->name; > > > 1055 (*map)->data.mux.function = np->name; > > > 1056 > > > 1057 if (PCS_HAS_PINCONF && function) { > > > 1058 res = pcs_parse_pinconf(pcs, np, function, map); > > > 1059 if (res) > > > 1060 goto free_pingroups; > > > 1061 *num_maps = 2; > > > 1062 } else { > > > 1063 *num_maps = 1; > > > 1064 } > > > > > > However, pcs_parse_pinconf() will also return 0 if !PCS_HAS_PINCONF or > > > !nconfs. I believe these conditions should indicate that no map was > > > added by returning -ENOTSUPP. Otherwise pcs_parse_one_pinctrl_entry() > > > will set num_maps = 2 even though no maps were successfully added, as > > > it does not reach "m++" on line 940: > > > > > > 895 static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > > > 896 struct pcs_function *func, > > > 897 struct pinctrl_map **map) > > > 898 > > > 899 { > > > 900 struct pinctrl_map *m = *map; > > > <snip> > > > 917 /* If pinconf isn't supported, don't parse properties in below. */ > > > 918 if (!PCS_HAS_PINCONF) > > > 919 return 0; > > > 920 > > > 921 /* cacluate how much properties are supported in current node */ > > > 922 for (i = 0; i < ARRAY_SIZE(prop2); i++) { > > > 923 if (of_find_property(np, prop2[i].name, NULL)) > > > 924 nconfs++; > > > 925 } > > > 926 for (i = 0; i < ARRAY_SIZE(prop4); i++) { > > > 927 if (of_find_property(np, prop4[i].name, NULL)) > > > 928 nconfs++; > > > 929 } > > > 930 if (!nconfs) > > > 919 return 0; > > > 932 > > > 933 func->conf = devm_kcalloc(pcs->dev, > > > 934 nconfs, sizeof(struct pcs_conf_vals), > > > 935 GFP_KERNEL); > > > 936 if (!func->conf) > > > 937 return -ENOMEM; > > > 938 func->nconfs = nconfs; > > > 939 conf = &(func->conf[0]); > > > 940 m++; > > > > > > This situtation will cause a boot failure [0] on the BeagleBone Black > > > (AM3358) when am33xx_pinmux node in arch/arm/boot/dts/am33xx-l4.dtsi > > > has compatible = "pinconf-single" instead of "pinctrl-single". > > > > > > The patch fixes this issue by returning -ENOSUPP when !PCS_HAS_PINCONF > > > or !nconfs, so that pcs_parse_one_pinctrl_entry() will know that no > > > map was added. > > > > > > Logic is also added to pcs_parse_one_pinctrl_entry() to distinguish > > > between -ENOSUPP and other errors. In the case of -ENOSUPP, num_maps > > > is set to 1 as it is valid for pinconf to be enabled and a given pin > > > group to not any pinconf properties. > > > > > > [0] https://lore.kernel.org/linux-omap/20200529175544.GA3766151@x1/ > > > > > > Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") > > > Signed-off-by: Drew Fustini <drew@beagleboard.org> > > > > Patch applied as non-critical (for-next) fix. > > > > If there is no hurry let's merge it this way with lots of testing > > along the way. > > > > Yours, > > Linus Walleij > > Thanks, I agree more testing is a good idea. > > In particular, do you have a way to followup with Haojian Zhuang within > Linaro? > Linus - do you have a way to contact Haojian Zhuan? I found them on Freenode but they have been idle since beginning of June. Last email I can find on the mailing list is from March. Tony and I would both like someone familiar with Hisilicon to comment on this patch as it is using pinctrl-single. Thanks, Drew
On Mon, 8 Jun 2020 at 20:51, Drew Fustini <drew@beagleboard.org> wrote: > > This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no > pinctrl_map is added. The current behavior is to return 0 when > !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() > incorrectly assumes that a map was added and sets num_maps = 2. > > Analysis: > ========= > The function pcs_parse_one_pinctrl_entry() calls pcs_parse_pinconf() > if PCS_HAS_PINCONF is enabled. The function pcs_parse_pinconf() > returns 0 to indicate there was no error and num_maps is then set to 2: > > 980 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, > 981 struct device_node *np, > 982 struct pinctrl_map **map, > 983 unsigned *num_maps, > 984 const char **pgnames) > 985 { > <snip> > 1053 (*map)->type = PIN_MAP_TYPE_MUX_GROUP; > 1054 (*map)->data.mux.group = np->name; > 1055 (*map)->data.mux.function = np->name; > 1056 > 1057 if (PCS_HAS_PINCONF && function) { > 1058 res = pcs_parse_pinconf(pcs, np, function, map); > 1059 if (res) > 1060 goto free_pingroups; > 1061 *num_maps = 2; > 1062 } else { > 1063 *num_maps = 1; > 1064 } > > However, pcs_parse_pinconf() will also return 0 if !PCS_HAS_PINCONF or > !nconfs. I believe these conditions should indicate that no map was > added by returning -ENOTSUPP. Otherwise pcs_parse_one_pinctrl_entry() > will set num_maps = 2 even though no maps were successfully added, as > it does not reach "m++" on line 940: > > 895 static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > 896 struct pcs_function *func, > 897 struct pinctrl_map **map) > 898 > 899 { > 900 struct pinctrl_map *m = *map; > <snip> > 917 /* If pinconf isn't supported, don't parse properties in below. */ > 918 if (!PCS_HAS_PINCONF) > 919 return 0; > 920 > 921 /* cacluate how much properties are supported in current node */ > 922 for (i = 0; i < ARRAY_SIZE(prop2); i++) { > 923 if (of_find_property(np, prop2[i].name, NULL)) > 924 nconfs++; > 925 } > 926 for (i = 0; i < ARRAY_SIZE(prop4); i++) { > 927 if (of_find_property(np, prop4[i].name, NULL)) > 928 nconfs++; > 929 } > 930 if (!nconfs) > 919 return 0; > 932 > 933 func->conf = devm_kcalloc(pcs->dev, > 934 nconfs, sizeof(struct pcs_conf_vals), > 935 GFP_KERNEL); > 936 if (!func->conf) > 937 return -ENOMEM; > 938 func->nconfs = nconfs; > 939 conf = &(func->conf[0]); > 940 m++; > > This situtation will cause a boot failure [0] on the BeagleBone Black > (AM3358) when am33xx_pinmux node in arch/arm/boot/dts/am33xx-l4.dtsi > has compatible = "pinconf-single" instead of "pinctrl-single". > > The patch fixes this issue by returning -ENOSUPP when !PCS_HAS_PINCONF > or !nconfs, so that pcs_parse_one_pinctrl_entry() will know that no > map was added. > > Logic is also added to pcs_parse_one_pinctrl_entry() to distinguish > between -ENOSUPP and other errors. In the case of -ENOSUPP, num_maps > is set to 1 as it is valid for pinconf to be enabled and a given pin > group to not any pinconf properties. > > [0] https://lore.kernel.org/linux-omap/20200529175544.GA3766151@x1/ > > Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") > Signed-off-by: Drew Fustini <drew@beagleboard.org> > --- > changes from V1 [0]: > - if pcs_parse_pinconf() returns -ENOSUPP, then set num_maps to 1 and > proceed normally as it is valid for group to have no pinconf props > - added Fixes: tag thanks to Gustavo A. R. Silva > > [0] https://lore.kernel.org/linux-omap/20200531204147.GA664833@x1/ > > drivers/pinctrl/pinctrl-single.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c > index 1e0614daee9b..a9d511982780 100644 > --- a/drivers/pinctrl/pinctrl-single.c > +++ b/drivers/pinctrl/pinctrl-single.c > @@ -916,7 +916,7 @@ static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > > /* If pinconf isn't supported, don't parse properties in below. */ > if (!PCS_HAS_PINCONF) > - return 0; > + return -ENOTSUPP; > > /* cacluate how much properties are supported in current node */ > for (i = 0; i < ARRAY_SIZE(prop2); i++) { > @@ -928,7 +928,7 @@ static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, > nconfs++; > } > if (!nconfs) > - return 0; > + return -ENOTSUPP; > > func->conf = devm_kcalloc(pcs->dev, > nconfs, sizeof(struct pcs_conf_vals), > @@ -1056,9 +1056,12 @@ static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, > > if (PCS_HAS_PINCONF && function) { > res = pcs_parse_pinconf(pcs, np, function, map); > - if (res) > + if (res == 0) > + *num_maps = 2; > + else if (res == -ENOTSUPP) > + *num_maps = 1; > + else > goto free_pingroups; > - *num_maps = 2; > } else { > *num_maps = 1; > } > -- > 2.25.1 Tested-by: Haojian Zhuang <haojian.zhuang@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c index 1e0614daee9b..a9d511982780 100644 --- a/drivers/pinctrl/pinctrl-single.c +++ b/drivers/pinctrl/pinctrl-single.c @@ -916,7 +916,7 @@ static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, /* If pinconf isn't supported, don't parse properties in below. */ if (!PCS_HAS_PINCONF) - return 0; + return -ENOTSUPP; /* cacluate how much properties are supported in current node */ for (i = 0; i < ARRAY_SIZE(prop2); i++) { @@ -928,7 +928,7 @@ static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, nconfs++; } if (!nconfs) - return 0; + return -ENOTSUPP; func->conf = devm_kcalloc(pcs->dev, nconfs, sizeof(struct pcs_conf_vals), @@ -1056,9 +1056,12 @@ static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, if (PCS_HAS_PINCONF && function) { res = pcs_parse_pinconf(pcs, np, function, map); - if (res) + if (res == 0) + *num_maps = 2; + else if (res == -ENOTSUPP) + *num_maps = 1; + else goto free_pingroups; - *num_maps = 2; } else { *num_maps = 1; }
This patch causes pcs_parse_pinconf() to return -ENOTSUPP when no pinctrl_map is added. The current behavior is to return 0 when !PCS_HAS_PINCONF or !nconfs. Thus pcs_parse_one_pinctrl_entry() incorrectly assumes that a map was added and sets num_maps = 2. Analysis: ========= The function pcs_parse_one_pinctrl_entry() calls pcs_parse_pinconf() if PCS_HAS_PINCONF is enabled. The function pcs_parse_pinconf() returns 0 to indicate there was no error and num_maps is then set to 2: 980 static int pcs_parse_one_pinctrl_entry(struct pcs_device *pcs, 981 struct device_node *np, 982 struct pinctrl_map **map, 983 unsigned *num_maps, 984 const char **pgnames) 985 { <snip> 1053 (*map)->type = PIN_MAP_TYPE_MUX_GROUP; 1054 (*map)->data.mux.group = np->name; 1055 (*map)->data.mux.function = np->name; 1056 1057 if (PCS_HAS_PINCONF && function) { 1058 res = pcs_parse_pinconf(pcs, np, function, map); 1059 if (res) 1060 goto free_pingroups; 1061 *num_maps = 2; 1062 } else { 1063 *num_maps = 1; 1064 } However, pcs_parse_pinconf() will also return 0 if !PCS_HAS_PINCONF or !nconfs. I believe these conditions should indicate that no map was added by returning -ENOTSUPP. Otherwise pcs_parse_one_pinctrl_entry() will set num_maps = 2 even though no maps were successfully added, as it does not reach "m++" on line 940: 895 static int pcs_parse_pinconf(struct pcs_device *pcs, struct device_node *np, 896 struct pcs_function *func, 897 struct pinctrl_map **map) 898 899 { 900 struct pinctrl_map *m = *map; <snip> 917 /* If pinconf isn't supported, don't parse properties in below. */ 918 if (!PCS_HAS_PINCONF) 919 return 0; 920 921 /* cacluate how much properties are supported in current node */ 922 for (i = 0; i < ARRAY_SIZE(prop2); i++) { 923 if (of_find_property(np, prop2[i].name, NULL)) 924 nconfs++; 925 } 926 for (i = 0; i < ARRAY_SIZE(prop4); i++) { 927 if (of_find_property(np, prop4[i].name, NULL)) 928 nconfs++; 929 } 930 if (!nconfs) 919 return 0; 932 933 func->conf = devm_kcalloc(pcs->dev, 934 nconfs, sizeof(struct pcs_conf_vals), 935 GFP_KERNEL); 936 if (!func->conf) 937 return -ENOMEM; 938 func->nconfs = nconfs; 939 conf = &(func->conf[0]); 940 m++; This situtation will cause a boot failure [0] on the BeagleBone Black (AM3358) when am33xx_pinmux node in arch/arm/boot/dts/am33xx-l4.dtsi has compatible = "pinconf-single" instead of "pinctrl-single". The patch fixes this issue by returning -ENOSUPP when !PCS_HAS_PINCONF or !nconfs, so that pcs_parse_one_pinctrl_entry() will know that no map was added. Logic is also added to pcs_parse_one_pinctrl_entry() to distinguish between -ENOSUPP and other errors. In the case of -ENOSUPP, num_maps is set to 1 as it is valid for pinconf to be enabled and a given pin group to not any pinconf properties. [0] https://lore.kernel.org/linux-omap/20200529175544.GA3766151@x1/ Fixes: 9dddb4df90d1 ("pinctrl: single: support generic pinconf") Signed-off-by: Drew Fustini <drew@beagleboard.org> --- changes from V1 [0]: - if pcs_parse_pinconf() returns -ENOSUPP, then set num_maps to 1 and proceed normally as it is valid for group to have no pinconf props - added Fixes: tag thanks to Gustavo A. R. Silva [0] https://lore.kernel.org/linux-omap/20200531204147.GA664833@x1/ drivers/pinctrl/pinctrl-single.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)