Message ID | 1491226922-20307-3-git-send-email-vivek.gautam@codeaurora.org |
---|---|
State | Superseded |
Headers | show |
Hi Vivek, thank you for the patch series. A few comments below: I'd like to reduce the API surface a bit and include the counting and array allocation in the _get functions, if possible. On Mon, 2017-04-03 at 19:12 +0530, Vivek Gautam wrote: > Many devices may want to request a bunch of resets > and control them. So it's better to manage them as an > array. Add APIs to _get(), _assert(), and _deassert() > an array of reset_control. > > Cc: Philipp Zabel <p.zabel@pengutronix.de> > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > --- > > Changes since v1: > - New patch added to the series. > > drivers/reset/core.c | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/reset.h | 108 ++++++++++++++++++++++++++++++++ > 2 files changed, 277 insertions(+) > > diff --git a/drivers/reset/core.c b/drivers/reset/core.c > index 66db061165cb..fb908aa4f69e 100644 > --- a/drivers/reset/core.c > +++ b/drivers/reset/core.c > @@ -477,3 +477,172 @@ int of_reset_control_get_count(struct device_node *node) > return count; > } > EXPORT_SYMBOL_GPL(of_reset_control_get_count); > + > +/* > + * APIs to manage an array of reset controllers > + */ > +/** > + * reset_control_array_assert: assert a list of resets > + * > + * @resets: reset control array holding info about a list of resets > + * @num_rsts: number of resets to be asserted. This should mention the API doesn't make any guarantees that the reset lines controlled by the reset array are asserted or deasserted in any particular order. > + * Returns 0 on success or error number on failure. > + */ > +int reset_control_array_assert(int num_rsts, > + struct reset_control_array *resets) I'd prefer to mirror the gpiod API a little, and to have the number contained in the array structure, similar to struct gpio_descs: struct reset_control_array { unsigned int num_rstcs; struct reset_control *rstc[]; }; int reset_control_array_assert(struct reset_control_array *resets) { ... > +{ > + int ret, i; > + > + if (WARN_ON(IS_ERR_OR_NULL(resets))) > + return -EINVAL; > + > + for (i = 0; i < num_rsts; i++) { > + ret = reset_control_assert(resets[i].rst); > + if (ret) > + return ret; > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(reset_control_array_assert); > + > +/** > + * reset_control_array_deassert: deassert a list of resets > + * > + * @resets: reset control array holding info about a list of resets > + * @num_rsts: number of resets to be deasserted. Same here, no guarantees on the order in which the resets are deasserted. > + * Returns 0 on success or error number on failure. > + */ > +int reset_control_array_deassert(int num_rsts, > + struct reset_control_array *resets) > +{ > + int ret, i; > + > + if (WARN_ON(IS_ERR_OR_NULL(resets))) > + return -EINVAL; > + > + for (i = 0; i < num_rsts; i++) > + ret = reset_control_deassert(resets[i].rst); > + if (ret) > + goto err; > + > + return 0; > + > +err: > + while (--i >= 0) > + reset_control_assert(resets[i].rst); > + return ret; > +} > +EXPORT_SYMBOL_GPL(reset_control_array_deassert); > + > +/** > + * reset_control_array_get - Get a list of reset controllers A list of "reset controls". > + * > + * @dev: device that requests the list of reset controllers > + * @num_rsts: number of reset controllers requested > + * @resets: reset control array holding info about a list of resets > + * @shared: whether reset controllers are shared or not > + * @optional: whether it is optional to get the reset controllers > + * This should mention that the array API is intended for a list of resets that just have to be asserted or deasserted, without any requirements on the order. > + * Returns 0 on success or error number on failure > + */ > +static int reset_control_array_get(struct device *dev, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional) Can we make this count and return a pointer to the newly created array? static struct reset_controls * reset_control_array_get(struct device *dev, bool shared, bool optional) { ... That way the consumer doesn't have to care about counting and array allocation. > +{ > + int ret, i; > + struct reset_control *rstc; > + > + for (i = 0; i < num_rsts; i++) { > + rstc = __of_reset_control_get(dev ? dev->of_node : NULL, > + resets[i].name, i, shared, optional); > + if (IS_ERR(rstc)) { > + ret = PTR_ERR(rstc); > + goto err_rst; > + } > + resets[i].rst = rstc; > + } > + > + return 0; > + > +err_rst: > + while (--i >= 0) > + reset_control_put(resets[i].rst); > + return ret; > +} > + > +static void devm_reset_control_array_release(struct device *dev, void *res) > +{ > + struct reset_control_devres *ptr = res; > + int i; > + > + for (i = 0; i < ptr->num_resets; i++) > + reset_control_put(ptr->resets[i].rst); > +} > + > +/** > + * devm_reset_control_array_get - Resource managed reset_control_array_get > + * See reset_control_array_get() for more > + * details > + * > + * Returns 0 on success or error number on failure > + */ > +int devm_reset_control_array_get(struct device *dev, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional) Same here. > +{ > + struct reset_control_devres *ptr; > + int ret; > + > + ptr = devres_alloc(devm_reset_control_array_release, sizeof(*ptr), > + GFP_KERNEL); > + if (!ptr) > + return -ENOMEM; > + > + ret = reset_control_array_get(dev, num_rsts, resets, > + shared, optional); > + if (ret) { > + ptr->resets = resets; > + ptr->num_resets = num_rsts; > + devres_add(dev, ptr); > + } else { > + devres_free(ptr); > + } > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(devm_reset_control_array_get); > + > +int of_reset_control_array_get(struct device_node *node, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional) And here. > +{ > + int ret, i; > + struct reset_control *rstc; > + > + for (i = 0; i < num_rsts; i++) { > + rstc = __of_reset_control_get(node, NULL, i, shared, optional); > + if (IS_ERR(rstc)) { > + ret = PTR_ERR(rstc); > + goto err_rst; > + } > + resets[i].rst = rstc; > + } > + > + return 0; > + > +err_rst: > + while (--i >= 0) > + reset_control_put(resets[i].rst); > + return ret; > +} > +EXPORT_SYMBOL_GPL(of_reset_control_array_get); > + > +void reset_control_array_put(int num, struct reset_control_array *resets) This could drop the num then. > +{ > + while (num--) > + reset_control_put(resets[num].rst); > +} > +EXPORT_SYMBOL_GPL(reset_control_array_put); > diff --git a/include/linux/reset.h b/include/linux/reset.h > index d89556412ccc..d6ca70b9d634 100644 > --- a/include/linux/reset.h > +++ b/include/linux/reset.h > @@ -5,6 +5,16 @@ > > struct reset_control; > > +struct reset_control_array { > + struct reset_control *rst; > + const char *name; Drop the name. This interface is only good for a bunch of anonymous resets that can all be asserted or deasserted in arbitrary order. If the reset lines have to be known individually, this is probably the wrong interface. > +}; > + > +struct reset_control_devres { > + struct reset_control_array *resets; > + int num_resets; > +}; > + > #ifdef CONFIG_RESET_CONTROLLER > > int reset_control_reset(struct reset_control *rstc); > @@ -23,6 +33,18 @@ struct reset_control *__devm_reset_control_get(struct device *dev, > int __must_check device_reset(struct device *dev); > int of_reset_control_get_count(struct device_node *node); > > +int reset_control_array_assert(int num_rsts, > + struct reset_control_array *resets); > +int reset_control_array_deassert(int num_rsts, > + struct reset_control_array *resets); > +int devm_reset_control_array_get(struct device *dev, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional); > +int of_reset_control_array_get(struct device_node *node, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional); > +void reset_control_array_put(int num, struct reset_control_array *resets); > + > static inline int device_reset_optional(struct device *dev) > { > return device_reset(dev); > @@ -85,6 +107,39 @@ static inline struct reset_control *__devm_reset_control_get( > return -ENOTSUPP; > } > > +static inline int reset_control_array_assert(int num_rsts, > + struct reset_control_array *resets) > +{ > + return 0; > +} > + > +static inline int reset_control_array_deassert(int num_rsts, > + struct reset_control_array *resets) > +{ > + return 0; > +} Is this missing a stub for reset_control_array_get? > +static inline > +int devm_reset_control_array_get(struct device *dev, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional) > +{ > + return optional ? NULL : ERR_PTR(-ENOTSUPP); > +} > + > +static inline > +int of_reset_control_array_get(struct device_node *node, int num_rsts, > + struct reset_control_array *resets, > + bool shared, bool optional) > +{ > + return optional ? NULL : ERR_PTR(-ENOTSUPP); > +} > + > +static inline > +void reset_control_array_put(int num, struct reset_control_array *resets) > +{ > +} > + > #endif /* CONFIG_RESET_CONTROLLER */ > > /** > @@ -374,4 +429,57 @@ static inline struct reset_control *devm_reset_control_get_by_index( > { > return devm_reset_control_get_exclusive_by_index(dev, index); > } > + > +/* > + * APIs to manage a list of reset controllers > + */ > +static inline > +int devm_reset_control_array_get_exclusive(struct device *dev, int num_rsts, > + struct reset_control_array *resets) > +{ > + return devm_reset_control_array_get(dev, num_rsts, > + resets, false, false); > +} > + > +static inline > +int devm_reset_control_array_get_shared(struct device *dev, int num_rsts, > + struct reset_control_array *resets) > +{ > + return devm_reset_control_array_get(dev, num_rsts, > + resets, true, false); > +} > + > +static inline > +int devm_reset_control_array_get_optional_exclusive(struct device *dev, > + int num_rsts, > + struct reset_control_array *resets) > +{ > + return devm_reset_control_array_get(dev, num_rsts, > + resets, false, true); > +} > + > +static inline > +int devm_reset_control_array_get_optional_shared(struct device *dev, > + int num_rsts, > + struct reset_control_array *resets) > +{ > + return devm_reset_control_array_get(dev, num_rsts, > + resets, true, true); > +} > + > +static inline > +int of_reset_control_array_get_exclusive(struct device_node *node, > + int num_rsts, > + struct reset_control_array *resets) > +{ > + return of_reset_control_array_get(node, num_rsts, resets, false, false); > +} > + > +static inline > +int of_reset_control_array_get_shared(struct device_node *node, > + int num_rsts, > + struct reset_control_array *resets) > +{ > + return of_reset_control_array_get(node, num_rsts, resets, true, false); > +} > #endif regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Vivek, [auto build test WARNING on balbi-usb/next] [also build test WARNING on v4.11-rc5 next-20170403] [cannot apply to pza/reset/next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Vivek-Gautam/reset-APIs-to-manage-a-list-of-resets/20170404-111639 base: https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git next config: x86_64-randconfig-x008-201714 (attached as .config) compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 reproduce: # save the attached .config to linux build tree make ARCH=x86_64 Note: it may well be a FALSE warning. FWIW you are at least aware of it now. http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings All warnings (new ones prefixed by >>): drivers/reset/core.c: In function 'reset_control_array_deassert': drivers/reset/core.c:526:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for (i = 0; i < num_rsts; i++) ^~~ drivers/reset/core.c:528:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' if (ret) ^~ >> drivers/reset/core.c:531:9: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized] return 0; ^ vim +/ret +531 drivers/reset/core.c 520 { 521 int ret, i; 522 523 if (WARN_ON(IS_ERR_OR_NULL(resets))) 524 return -EINVAL; 525 > 526 for (i = 0; i < num_rsts; i++) 527 ret = reset_control_deassert(resets[i].rst); 528 if (ret) 529 goto err; 530 > 531 return 0; 532 533 err: 534 while (--i >= 0) --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
Hi Vivek, [auto build test WARNING on balbi-usb/next] [also build test WARNING on v4.11-rc5 next-20170403] [cannot apply to pza/reset/next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Vivek-Gautam/reset-APIs-to-manage-a-list-of-resets/20170404-111639 base: https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git next config: x86_64-randconfig-x004-201714 (attached as .config) compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 reproduce: # save the attached .config to linux build tree make ARCH=x86_64 All warnings (new ones prefixed by >>): drivers/reset/core.c: In function 'reset_control_array_deassert': >> drivers/reset/core.c:526:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation] for (i = 0; i < num_rsts; i++) ^~~ drivers/reset/core.c:528:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' if (ret) ^~ vim +/for +526 drivers/reset/core.c 510 /** 511 * reset_control_array_deassert: deassert a list of resets 512 * 513 * @resets: reset control array holding info about a list of resets 514 * @num_rsts: number of resets to be deasserted. 515 * 516 * Returns 0 on success or error number on failure. 517 */ 518 int reset_control_array_deassert(int num_rsts, 519 struct reset_control_array *resets) 520 { 521 int ret, i; 522 523 if (WARN_ON(IS_ERR_OR_NULL(resets))) 524 return -EINVAL; 525 > 526 for (i = 0; i < num_rsts; i++) 527 ret = reset_control_deassert(resets[i].rst); 528 if (ret) 529 goto err; 530 531 return 0; 532 533 err: 534 while (--i >= 0) --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
On 04/04/2017 09:44 AM, kbuild test robot wrote: > Hi Vivek, > > [auto build test WARNING on balbi-usb/next] > [also build test WARNING on v4.11-rc5 next-20170403] > [cannot apply to pza/reset/next] > [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] > > url: https://github.com/0day-ci/linux/commits/Vivek-Gautam/reset-APIs-to-manage-a-list-of-resets/20170404-111639 > base: https://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb.git next > config: x86_64-randconfig-x004-201714 (attached as .config) > compiler: gcc-6 (Debian 6.2.0-3) 6.2.0 20160901 > reproduce: > # save the attached .config to linux build tree > make ARCH=x86_64 > > All warnings (new ones prefixed by >>): > > drivers/reset/core.c: In function 'reset_control_array_deassert': >>> drivers/reset/core.c:526:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation] > for (i = 0; i < num_rsts; i++) > ^~~ > drivers/reset/core.c:528:3: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for' > if (ret) > ^~ Right, gonna fix these warnings in the next version of the patch. Thanks > vim +/for +526 drivers/reset/core.c > > 510 /** > 511 * reset_control_array_deassert: deassert a list of resets > 512 * > 513 * @resets: reset control array holding info about a list of resets > 514 * @num_rsts: number of resets to be deasserted. > 515 * > 516 * Returns 0 on success or error number on failure. > 517 */ > 518 int reset_control_array_deassert(int num_rsts, > 519 struct reset_control_array *resets) > 520 { > 521 int ret, i; > 522 > 523 if (WARN_ON(IS_ERR_OR_NULL(resets))) > 524 return -EINVAL; > 525 > > 526 for (i = 0; i < num_rsts; i++) > 527 ret = reset_control_deassert(resets[i].rst); > 528 if (ret) > 529 goto err; > 530 > 531 return 0; > 532 > 533 err: > 534 while (--i >= 0) > > --- > 0-DAY kernel test infrastructure Open Source Technology Center > https://lists.01.org/pipermail/kbuild-all Intel Corporation BRs Vivek
Hi Philipp, On 04/03/2017 10:06 PM, Philipp Zabel wrote: > Hi Vivek, > > thank you for the patch series. A few comments below: I'd like to reduce > the API surface a bit and include the counting and array allocation in > the _get functions, if possible. Thank you for reviewing the patch. Please find my comments inline. > > On Mon, 2017-04-03 at 19:12 +0530, Vivek Gautam wrote: >> Many devices may want to request a bunch of resets >> and control them. So it's better to manage them as an >> array. Add APIs to _get(), _assert(), and _deassert() >> an array of reset_control. >> >> Cc: Philipp Zabel <p.zabel@pengutronix.de> >> Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> >> --- >> >> Changes since v1: >> - New patch added to the series. >> >> drivers/reset/core.c | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++ >> include/linux/reset.h | 108 ++++++++++++++++++++++++++++++++ >> 2 files changed, 277 insertions(+) >> >> diff --git a/drivers/reset/core.c b/drivers/reset/core.c >> index 66db061165cb..fb908aa4f69e 100644 >> --- a/drivers/reset/core.c >> +++ b/drivers/reset/core.c >> @@ -477,3 +477,172 @@ int of_reset_control_get_count(struct device_node *node) >> return count; >> } >> EXPORT_SYMBOL_GPL(of_reset_control_get_count); >> + >> +/* >> + * APIs to manage an array of reset controllers >> + */ >> +/** >> + * reset_control_array_assert: assert a list of resets >> + * >> + * @resets: reset control array holding info about a list of resets >> + * @num_rsts: number of resets to be asserted. > This should mention the API doesn't make any guarantees that the reset > lines controlled by the reset array are asserted or deasserted in any > particular order. Sure, will add this comment. > >> + * Returns 0 on success or error number on failure. >> + */ >> +int reset_control_array_assert(int num_rsts, >> + struct reset_control_array *resets) > I'd prefer to mirror the gpiod API a little, and to have the number > contained in the array structure, similar to struct gpio_descs: > > struct reset_control_array { > unsigned int num_rstcs; > struct reset_control *rstc[]; > }; > > int reset_control_array_assert(struct reset_control_array *resets) > { > ... Alright, i can update this. I took regulator_bulk interface as the reference, but now i see gpio_descs has a smaller footprint. >> +{ >> + int ret, i; >> + >> + if (WARN_ON(IS_ERR_OR_NULL(resets))) >> + return -EINVAL; >> + >> + for (i = 0; i < num_rsts; i++) { >> + ret = reset_control_assert(resets[i].rst); >> + if (ret) >> + return ret; >> + } >> + >> + return 0; >> +} >> +EXPORT_SYMBOL_GPL(reset_control_array_assert); >> + >> +/** >> + * reset_control_array_deassert: deassert a list of resets >> + * >> + * @resets: reset control array holding info about a list of resets >> + * @num_rsts: number of resets to be deasserted. > Same here, no guarantees on the order in which the resets are > deasserted. sure. > >> + * Returns 0 on success or error number on failure. >> + */ >> +int reset_control_array_deassert(int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + int ret, i; >> + >> + if (WARN_ON(IS_ERR_OR_NULL(resets))) >> + return -EINVAL; >> + >> + for (i = 0; i < num_rsts; i++) >> + ret = reset_control_deassert(resets[i].rst); >> + if (ret) >> + goto err; >> + >> + return 0; >> + >> +err: >> + while (--i >= 0) >> + reset_control_assert(resets[i].rst); >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(reset_control_array_deassert); >> + >> +/** >> + * reset_control_array_get - Get a list of reset controllers > A list of "reset controls". right, will update this. > >> + * >> + * @dev: device that requests the list of reset controllers >> + * @num_rsts: number of reset controllers requested >> + * @resets: reset control array holding info about a list of resets >> + * @shared: whether reset controllers are shared or not >> + * @optional: whether it is optional to get the reset controllers >> + * > This should mention that the array API is intended for a list of resets > that just have to be asserted or deasserted, without any requirements on > the order. Sure, will mention that. > >> + * Returns 0 on success or error number on failure >> + */ >> +static int reset_control_array_get(struct device *dev, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional) > Can we make this count and return a pointer to the newly created array? > > static struct reset_controls * > reset_control_array_get(struct device *dev, bool shared, bool optional) > { > ... > > That way the consumer doesn't have to care about counting and array > allocation. Just trying to think again in line with the regulator bulk APIs. Can't a user provide a list of reset controls as data and thus request reset controls with a "id" and num_resets available. e.g. const char * const rst_names[] = { "rst1", "rst2" ... }; xyz_data = { .resets = rst_names; .num = ARRAY_SIZE(rst_names); }; and then the driver making use of reset_control_array APIs to request this list of reset controls and assert/deassert them. I am assuming this case when one user driver is used across a bunch of platforms with different number of resets available. We may not want to rely solely on the device tree entries, since the resets can be mandatory in few cases and we may want to return failure. > >> +{ >> + int ret, i; >> + struct reset_control *rstc; >> + >> + for (i = 0; i < num_rsts; i++) { >> + rstc = __of_reset_control_get(dev ? dev->of_node : NULL, >> + resets[i].name, i, shared, optional); >> + if (IS_ERR(rstc)) { >> + ret = PTR_ERR(rstc); >> + goto err_rst; >> + } >> + resets[i].rst = rstc; >> + } >> + >> + return 0; >> + >> +err_rst: >> + while (--i >= 0) >> + reset_control_put(resets[i].rst); >> + return ret; >> +} >> + >> +static void devm_reset_control_array_release(struct device *dev, void *res) >> +{ >> + struct reset_control_devres *ptr = res; >> + int i; >> + >> + for (i = 0; i < ptr->num_resets; i++) >> + reset_control_put(ptr->resets[i].rst); >> +} >> + >> +/** >> + * devm_reset_control_array_get - Resource managed reset_control_array_get >> + * See reset_control_array_get() for more >> + * details >> + * >> + * Returns 0 on success or error number on failure >> + */ >> +int devm_reset_control_array_get(struct device *dev, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional) > Same here. > >> +{ >> + struct reset_control_devres *ptr; >> + int ret; >> + >> + ptr = devres_alloc(devm_reset_control_array_release, sizeof(*ptr), >> + GFP_KERNEL); >> + if (!ptr) >> + return -ENOMEM; >> + >> + ret = reset_control_array_get(dev, num_rsts, resets, >> + shared, optional); >> + if (ret) { >> + ptr->resets = resets; >> + ptr->num_resets = num_rsts; >> + devres_add(dev, ptr); >> + } else { >> + devres_free(ptr); >> + } >> + >> + return 0; >> +} >> +EXPORT_SYMBOL_GPL(devm_reset_control_array_get); >> + >> +int of_reset_control_array_get(struct device_node *node, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional) > And here. > >> +{ >> + int ret, i; >> + struct reset_control *rstc; >> + >> + for (i = 0; i < num_rsts; i++) { >> + rstc = __of_reset_control_get(node, NULL, i, shared, optional); >> + if (IS_ERR(rstc)) { >> + ret = PTR_ERR(rstc); >> + goto err_rst; >> + } >> + resets[i].rst = rstc; >> + } >> + >> + return 0; >> + >> +err_rst: >> + while (--i >= 0) >> + reset_control_put(resets[i].rst); >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(of_reset_control_array_get); >> + >> +void reset_control_array_put(int num, struct reset_control_array *resets) > This could drop the num then. Sure. > >> +{ >> + while (num--) >> + reset_control_put(resets[num].rst); >> +} >> +EXPORT_SYMBOL_GPL(reset_control_array_put); >> diff --git a/include/linux/reset.h b/include/linux/reset.h >> index d89556412ccc..d6ca70b9d634 100644 >> --- a/include/linux/reset.h >> +++ b/include/linux/reset.h >> @@ -5,6 +5,16 @@ >> >> struct reset_control; >> >> +struct reset_control_array { >> + struct reset_control *rst; >> + const char *name; > Drop the name. This interface is only good for a bunch of anonymous > resets that can all be asserted or deasserted in arbitrary order. If the > reset lines have to be known individually, this is probably the wrong > interface. Sure, will drop 'name' and have the reset_control_array structure as suggested above. > >> +}; >> + >> +struct reset_control_devres { >> + struct reset_control_array *resets; >> + int num_resets; >> +}; >> + >> #ifdef CONFIG_RESET_CONTROLLER >> >> int reset_control_reset(struct reset_control *rstc); >> @@ -23,6 +33,18 @@ struct reset_control *__devm_reset_control_get(struct device *dev, >> int __must_check device_reset(struct device *dev); >> int of_reset_control_get_count(struct device_node *node); >> >> +int reset_control_array_assert(int num_rsts, >> + struct reset_control_array *resets); >> +int reset_control_array_deassert(int num_rsts, >> + struct reset_control_array *resets); >> +int devm_reset_control_array_get(struct device *dev, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional); >> +int of_reset_control_array_get(struct device_node *node, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional); >> +void reset_control_array_put(int num, struct reset_control_array *resets); >> + >> static inline int device_reset_optional(struct device *dev) >> { >> return device_reset(dev); >> @@ -85,6 +107,39 @@ static inline struct reset_control *__devm_reset_control_get( >> return -ENOTSUPP; >> } >> >> +static inline int reset_control_array_assert(int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return 0; >> +} >> + >> +static inline int reset_control_array_deassert(int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return 0; >> +} > Is this missing a stub for reset_control_array_get? No, that's supposed to be a static function. > >> +static inline >> +int devm_reset_control_array_get(struct device *dev, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional) >> +{ >> + return optional ? NULL : ERR_PTR(-ENOTSUPP); >> +} >> + >> +static inline >> +int of_reset_control_array_get(struct device_node *node, int num_rsts, >> + struct reset_control_array *resets, >> + bool shared, bool optional) >> +{ >> + return optional ? NULL : ERR_PTR(-ENOTSUPP); >> +} >> + >> +static inline >> +void reset_control_array_put(int num, struct reset_control_array *resets) >> +{ >> +} >> + >> #endif /* CONFIG_RESET_CONTROLLER */ >> >> /** >> @@ -374,4 +429,57 @@ static inline struct reset_control *devm_reset_control_get_by_index( >> { >> return devm_reset_control_get_exclusive_by_index(dev, index); >> } >> + >> +/* >> + * APIs to manage a list of reset controllers >> + */ >> +static inline >> +int devm_reset_control_array_get_exclusive(struct device *dev, int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return devm_reset_control_array_get(dev, num_rsts, >> + resets, false, false); >> +} >> + >> +static inline >> +int devm_reset_control_array_get_shared(struct device *dev, int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return devm_reset_control_array_get(dev, num_rsts, >> + resets, true, false); >> +} >> + >> +static inline >> +int devm_reset_control_array_get_optional_exclusive(struct device *dev, >> + int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return devm_reset_control_array_get(dev, num_rsts, >> + resets, false, true); >> +} >> + >> +static inline >> +int devm_reset_control_array_get_optional_shared(struct device *dev, >> + int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return devm_reset_control_array_get(dev, num_rsts, >> + resets, true, true); >> +} >> + >> +static inline >> +int of_reset_control_array_get_exclusive(struct device_node *node, >> + int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return of_reset_control_array_get(node, num_rsts, resets, false, false); >> +} >> + >> +static inline >> +int of_reset_control_array_get_shared(struct device_node *node, >> + int num_rsts, >> + struct reset_control_array *resets) >> +{ >> + return of_reset_control_array_get(node, num_rsts, resets, true, false); >> +} >> #endif > regards > Philipp > Best Regards Vivek
Hi Vivek, On Tue, 2017-04-04 at 16:09 +0530, Vivek Gautam wrote: [...] > > I'd prefer to mirror the gpiod API a little, and to have the number > > contained in the array structure, similar to struct gpio_descs: [...] > Alright, i can update this. > I took regulator_bulk interface as the reference, but now i see > gpio_descs has a smaller footprint. Ok, understood. I think the smaller footprint API is more convenient for the user. [...] > >> + * Returns 0 on success or error number on failure > >> + */ > >> +static int reset_control_array_get(struct device *dev, int num_rsts, > >> + struct reset_control_array *resets, > >> + bool shared, bool optional) > > Can we make this count and return a pointer to the newly created array? > > > > static struct reset_controls * > > reset_control_array_get(struct device *dev, bool shared, bool optional) > > { > > ... > > > > That way the consumer doesn't have to care about counting and array > > allocation. > > Just trying to think again in line with the regulator bulk APIs. > Can't a user provide a list of reset controls as data and thus > request reset controls with a "id" and num_resets available. > > e.g. > const char * const rst_names[] = { > "rst1", "rst2" ... > }; > xyz_data = { > .resets = rst_names; > .num = ARRAY_SIZE(rst_names); > }; > and then the driver making use of reset_control_array APIs > to request this list of reset controls and assert/deassert them. > > I am assuming this case when one user driver is used across a bunch > of platforms with different number of resets available. > We may not want to rely solely on the device tree entries, since > the resets can be mandatory in few cases and we may want to > return failure. The way I understood the array API was as a method of handling a list of anonymous resets, specified as resets = <&reset 1>, <&reset 2>, <&reset 3>; // reset-names = "rst1", "rst2", "rst3"; /* don't care */ in the device tree. Now if you want to handle a partial list of those as an unordered list, with special consideration for others, that could be added as a separate API when there is use for it. But I expect that most potential users of this array API will not have to make such a distinction. > >> @@ -85,6 +107,39 @@ static inline struct reset_control *__devm_reset_control_get( > >> return -ENOTSUPP; > >> } > >> > >> +static inline int reset_control_array_assert(int num_rsts, > >> + struct reset_control_array *resets) > >> +{ > >> + return 0; > >> +} > >> + > >> +static inline int reset_control_array_deassert(int num_rsts, > >> + struct reset_control_array *resets) > >> +{ > >> + return 0; > >> +} > > Is this missing a stub for reset_control_array_get? > > No, that's supposed to be a static function. Oh right, it is static. Please ignore. regards Philipp -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Philipp, On 04/04/2017 06:17 PM, Philipp Zabel wrote: > Hi Vivek, > > On Tue, 2017-04-04 at 16:09 +0530, Vivek Gautam wrote: > [...] >>> I'd prefer to mirror the gpiod API a little, and to have the number >>> contained in the array structure, similar to struct gpio_descs: > [...] >> Alright, i can update this. >> I took regulator_bulk interface as the reference, but now i see >> gpio_descs has a smaller footprint. > Ok, understood. > I think the smaller footprint API is more convenient for the user. > > [...] >>>> + * Returns 0 on success or error number on failure >>>> + */ >>>> +static int reset_control_array_get(struct device *dev, int num_rsts, >>>> + struct reset_control_array *resets, >>>> + bool shared, bool optional) >>> Can we make this count and return a pointer to the newly created array? >>> >>> static struct reset_controls * >>> reset_control_array_get(struct device *dev, bool shared, bool optional) >>> { >>> ... >>> >>> That way the consumer doesn't have to care about counting and array >>> allocation. >> Just trying to think again in line with the regulator bulk APIs. >> Can't a user provide a list of reset controls as data and thus >> request reset controls with a "id" and num_resets available. >> >> e.g. >> const char * const rst_names[] = { >> "rst1", "rst2" ... >> }; >> xyz_data = { >> .resets = rst_names; >> .num = ARRAY_SIZE(rst_names); >> }; >> and then the driver making use of reset_control_array APIs >> to request this list of reset controls and assert/deassert them. >> >> I am assuming this case when one user driver is used across a bunch >> of platforms with different number of resets available. >> We may not want to rely solely on the device tree entries, since >> the resets can be mandatory in few cases and we may want to >> return failure. > The way I understood the array API was as a method of handling a list of > anonymous resets, specified as > > resets = <&reset 1>, <&reset 2>, <&reset 3>; > // reset-names = "rst1", "rst2", "rst3"; /* don't care */ > > in the device tree. > > Now if you want to handle a partial list of those as an unordered list, > with special consideration for others, that could be added as a separate > API when there is use for it. But I expect that most potential users of > this array API will not have to make such a distinction. Alright, I will modify the array APIs as suggested to handle an unordered list of resets passed from the device tree. As you said, we can handle the special cases when the need arise. > >>>> @@ -85,6 +107,39 @@ static inline struct reset_control *__devm_reset_control_get( >>>> return -ENOTSUPP; >>>> } >>>> >>>> +static inline int reset_control_array_assert(int num_rsts, >>>> + struct reset_control_array *resets) >>>> +{ >>>> + return 0; >>>> +} >>>> + >>>> +static inline int reset_control_array_deassert(int num_rsts, >>>> + struct reset_control_array *resets) >>>> +{ >>>> + return 0; >>>> +} >>> Is this missing a stub for reset_control_array_get? >> No, that's supposed to be a static function. > Oh right, it is static. Please ignore. Thanks > regards > Philipp > Best Regards Vivek
diff --git a/drivers/reset/core.c b/drivers/reset/core.c index 66db061165cb..fb908aa4f69e 100644 --- a/drivers/reset/core.c +++ b/drivers/reset/core.c @@ -477,3 +477,172 @@ int of_reset_control_get_count(struct device_node *node) return count; } EXPORT_SYMBOL_GPL(of_reset_control_get_count); + +/* + * APIs to manage an array of reset controllers + */ +/** + * reset_control_array_assert: assert a list of resets + * + * @resets: reset control array holding info about a list of resets + * @num_rsts: number of resets to be asserted. + * + * Returns 0 on success or error number on failure. + */ +int reset_control_array_assert(int num_rsts, + struct reset_control_array *resets) +{ + int ret, i; + + if (WARN_ON(IS_ERR_OR_NULL(resets))) + return -EINVAL; + + for (i = 0; i < num_rsts; i++) { + ret = reset_control_assert(resets[i].rst); + if (ret) + return ret; + } + + return 0; +} +EXPORT_SYMBOL_GPL(reset_control_array_assert); + +/** + * reset_control_array_deassert: deassert a list of resets + * + * @resets: reset control array holding info about a list of resets + * @num_rsts: number of resets to be deasserted. + * + * Returns 0 on success or error number on failure. + */ +int reset_control_array_deassert(int num_rsts, + struct reset_control_array *resets) +{ + int ret, i; + + if (WARN_ON(IS_ERR_OR_NULL(resets))) + return -EINVAL; + + for (i = 0; i < num_rsts; i++) + ret = reset_control_deassert(resets[i].rst); + if (ret) + goto err; + + return 0; + +err: + while (--i >= 0) + reset_control_assert(resets[i].rst); + return ret; +} +EXPORT_SYMBOL_GPL(reset_control_array_deassert); + +/** + * reset_control_array_get - Get a list of reset controllers + * + * @dev: device that requests the list of reset controllers + * @num_rsts: number of reset controllers requested + * @resets: reset control array holding info about a list of resets + * @shared: whether reset controllers are shared or not + * @optional: whether it is optional to get the reset controllers + * + * Returns 0 on success or error number on failure + */ +static int reset_control_array_get(struct device *dev, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional) +{ + int ret, i; + struct reset_control *rstc; + + for (i = 0; i < num_rsts; i++) { + rstc = __of_reset_control_get(dev ? dev->of_node : NULL, + resets[i].name, i, shared, optional); + if (IS_ERR(rstc)) { + ret = PTR_ERR(rstc); + goto err_rst; + } + resets[i].rst = rstc; + } + + return 0; + +err_rst: + while (--i >= 0) + reset_control_put(resets[i].rst); + return ret; +} + +static void devm_reset_control_array_release(struct device *dev, void *res) +{ + struct reset_control_devres *ptr = res; + int i; + + for (i = 0; i < ptr->num_resets; i++) + reset_control_put(ptr->resets[i].rst); +} + +/** + * devm_reset_control_array_get - Resource managed reset_control_array_get + * See reset_control_array_get() for more + * details + * + * Returns 0 on success or error number on failure + */ +int devm_reset_control_array_get(struct device *dev, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional) +{ + struct reset_control_devres *ptr; + int ret; + + ptr = devres_alloc(devm_reset_control_array_release, sizeof(*ptr), + GFP_KERNEL); + if (!ptr) + return -ENOMEM; + + ret = reset_control_array_get(dev, num_rsts, resets, + shared, optional); + if (ret) { + ptr->resets = resets; + ptr->num_resets = num_rsts; + devres_add(dev, ptr); + } else { + devres_free(ptr); + } + + return 0; +} +EXPORT_SYMBOL_GPL(devm_reset_control_array_get); + +int of_reset_control_array_get(struct device_node *node, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional) +{ + int ret, i; + struct reset_control *rstc; + + for (i = 0; i < num_rsts; i++) { + rstc = __of_reset_control_get(node, NULL, i, shared, optional); + if (IS_ERR(rstc)) { + ret = PTR_ERR(rstc); + goto err_rst; + } + resets[i].rst = rstc; + } + + return 0; + +err_rst: + while (--i >= 0) + reset_control_put(resets[i].rst); + return ret; +} +EXPORT_SYMBOL_GPL(of_reset_control_array_get); + +void reset_control_array_put(int num, struct reset_control_array *resets) +{ + while (num--) + reset_control_put(resets[num].rst); +} +EXPORT_SYMBOL_GPL(reset_control_array_put); diff --git a/include/linux/reset.h b/include/linux/reset.h index d89556412ccc..d6ca70b9d634 100644 --- a/include/linux/reset.h +++ b/include/linux/reset.h @@ -5,6 +5,16 @@ struct reset_control; +struct reset_control_array { + struct reset_control *rst; + const char *name; +}; + +struct reset_control_devres { + struct reset_control_array *resets; + int num_resets; +}; + #ifdef CONFIG_RESET_CONTROLLER int reset_control_reset(struct reset_control *rstc); @@ -23,6 +33,18 @@ struct reset_control *__devm_reset_control_get(struct device *dev, int __must_check device_reset(struct device *dev); int of_reset_control_get_count(struct device_node *node); +int reset_control_array_assert(int num_rsts, + struct reset_control_array *resets); +int reset_control_array_deassert(int num_rsts, + struct reset_control_array *resets); +int devm_reset_control_array_get(struct device *dev, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional); +int of_reset_control_array_get(struct device_node *node, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional); +void reset_control_array_put(int num, struct reset_control_array *resets); + static inline int device_reset_optional(struct device *dev) { return device_reset(dev); @@ -85,6 +107,39 @@ static inline struct reset_control *__devm_reset_control_get( return -ENOTSUPP; } +static inline int reset_control_array_assert(int num_rsts, + struct reset_control_array *resets) +{ + return 0; +} + +static inline int reset_control_array_deassert(int num_rsts, + struct reset_control_array *resets) +{ + return 0; +} + +static inline +int devm_reset_control_array_get(struct device *dev, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + +static inline +int of_reset_control_array_get(struct device_node *node, int num_rsts, + struct reset_control_array *resets, + bool shared, bool optional) +{ + return optional ? NULL : ERR_PTR(-ENOTSUPP); +} + +static inline +void reset_control_array_put(int num, struct reset_control_array *resets) +{ +} + #endif /* CONFIG_RESET_CONTROLLER */ /** @@ -374,4 +429,57 @@ static inline struct reset_control *devm_reset_control_get_by_index( { return devm_reset_control_get_exclusive_by_index(dev, index); } + +/* + * APIs to manage a list of reset controllers + */ +static inline +int devm_reset_control_array_get_exclusive(struct device *dev, int num_rsts, + struct reset_control_array *resets) +{ + return devm_reset_control_array_get(dev, num_rsts, + resets, false, false); +} + +static inline +int devm_reset_control_array_get_shared(struct device *dev, int num_rsts, + struct reset_control_array *resets) +{ + return devm_reset_control_array_get(dev, num_rsts, + resets, true, false); +} + +static inline +int devm_reset_control_array_get_optional_exclusive(struct device *dev, + int num_rsts, + struct reset_control_array *resets) +{ + return devm_reset_control_array_get(dev, num_rsts, + resets, false, true); +} + +static inline +int devm_reset_control_array_get_optional_shared(struct device *dev, + int num_rsts, + struct reset_control_array *resets) +{ + return devm_reset_control_array_get(dev, num_rsts, + resets, true, true); +} + +static inline +int of_reset_control_array_get_exclusive(struct device_node *node, + int num_rsts, + struct reset_control_array *resets) +{ + return of_reset_control_array_get(node, num_rsts, resets, false, false); +} + +static inline +int of_reset_control_array_get_shared(struct device_node *node, + int num_rsts, + struct reset_control_array *resets) +{ + return of_reset_control_array_get(node, num_rsts, resets, true, false); +} #endif
Many devices may want to request a bunch of resets and control them. So it's better to manage them as an array. Add APIs to _get(), _assert(), and _deassert() an array of reset_control. Cc: Philipp Zabel <p.zabel@pengutronix.de> Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> --- Changes since v1: - New patch added to the series. drivers/reset/core.c | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/reset.h | 108 ++++++++++++++++++++++++++++++++ 2 files changed, 277 insertions(+)