| Message ID | 1449126330-21595-1-git-send-email-wens@csie.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, On Thu, Dec 03, 2015 at 03:05:30PM +0800, Chen-Yu Tsai wrote: > The APBS clock on sun9i is the same as the APB0 clock on sun8i. With > sun9i we are supporting the PRCM clocks by using CLK_OF_DECLARE, > instead of through a PRCM mfd device and subdevices for each clock > and reset control. As such we need a CLK_OF_DECLARE version of > the sun8i-a23-apb0-clk driver. > > Also, build it for sun9i/A80, and not just for configurations with > MFD_SUN6I_PRCM enabled. > > Signed-off-by: Chen-Yu Tsai <wens@csie.org> > --- > > Changes since v4: > > - Keep building clk-sun8i-apb0 for SUN6I_MFD_PRCM. > > - Add an error message and comment for when of_io_request_and_map() > fails. of_io_request_and_map() merges a bunch of errors into -EINVAL, > so this might not be the best approach. But I think having an error > message when we know something is wrong (-EBUSY, -ENOMEM) is better. > > --- > drivers/clk/sunxi/Makefile | 1 + > drivers/clk/sunxi/clk-sun8i-apb0.c | 80 ++++++++++++++++++++++++++++++++------ > 2 files changed, 69 insertions(+), 12 deletions(-) > > diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile > index 103efab05ca8..ccf21ba3b6b0 100644 > --- a/drivers/clk/sunxi/Makefile > +++ b/drivers/clk/sunxi/Makefile > @@ -15,6 +15,7 @@ obj-y += clk-sun9i-core.o > obj-y += clk-sun9i-mmc.o > obj-y += clk-usb.o > > +obj-$(CONFIG_MACH_SUN9I) += clk-sun8i-apb0.o > obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-cpus.o > > obj-$(CONFIG_MFD_SUN6I_PRCM) += \ > diff --git a/drivers/clk/sunxi/clk-sun8i-apb0.c b/drivers/clk/sunxi/clk-sun8i-apb0.c > index 7ae5d2c2cde1..7ba61103a6f5 100644 > --- a/drivers/clk/sunxi/clk-sun8i-apb0.c > +++ b/drivers/clk/sunxi/clk-sun8i-apb0.c > @@ -17,13 +17,77 @@ > #include <linux/clk-provider.h> > #include <linux/module.h> > #include <linux/of.h> > +#include <linux/of_address.h> > #include <linux/platform_device.h> > > +static struct clk *sun8i_a23_apb0_register(struct device_node *node, > + void __iomem *reg) > +{ > + const char *clk_name = node->name; > + const char *clk_parent; > + struct clk *clk; > + int ret; > + > + clk_parent = of_clk_get_parent_name(node, 0); > + if (!clk_parent) > + return ERR_PTR(-EINVAL); > + > + of_property_read_string(node, "clock-output-names", &clk_name); > + > + /* The A23 APB0 clock is a standard 2 bit wide divider clock */ > + clk = clk_register_divider(NULL, clk_name, clk_parent, 0, reg, > + 0, 2, CLK_DIVIDER_POWER_OF_TWO, NULL); > + if (IS_ERR(clk)) > + return clk; > + > + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk); > + if (ret) > + goto err_unregister; > + > + return clk; > + > +err_unregister: > + clk_unregister_divider(clk); > + > + return ERR_PTR(ret); > +} > + > +static void sun8i_a23_apb0_setup(struct device_node *node) > +{ > + void __iomem *reg; > + struct resource res; > + struct clk *clk; > + > + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); > + if (IS_ERR(reg)) { > + /* > + * This happens with clk nodes instantiated through mfd, > + * as those do not have their resources assigned in the > + * device tree. Do not print an error in this case. > + */ > + if (PTR_ERR(reg) != -EINVAL) > + pr_err("Could not get registers for a23-apb0-clk\n"); This is not the only case you have to take into account. There's also the case when you have a regular clock (and by regular I mean that is not in the PRCM) that will be probed by the CLK_OF_DECLARE mechanism and then later by the device model. In such a case, the second of_io_request_and_map will fail, and you will have an error returned that you do not ignore at the moment. Maxime
On Mon, Dec 7, 2015 at 5:36 PM, Maxime Ripard <maxime.ripard@free-electrons.com> wrote: > Hi, > > On Thu, Dec 03, 2015 at 03:05:30PM +0800, Chen-Yu Tsai wrote: >> The APBS clock on sun9i is the same as the APB0 clock on sun8i. With >> sun9i we are supporting the PRCM clocks by using CLK_OF_DECLARE, >> instead of through a PRCM mfd device and subdevices for each clock >> and reset control. As such we need a CLK_OF_DECLARE version of >> the sun8i-a23-apb0-clk driver. >> >> Also, build it for sun9i/A80, and not just for configurations with >> MFD_SUN6I_PRCM enabled. >> >> Signed-off-by: Chen-Yu Tsai <wens@csie.org> >> --- >> >> Changes since v4: >> >> - Keep building clk-sun8i-apb0 for SUN6I_MFD_PRCM. >> >> - Add an error message and comment for when of_io_request_and_map() >> fails. of_io_request_and_map() merges a bunch of errors into -EINVAL, >> so this might not be the best approach. But I think having an error >> message when we know something is wrong (-EBUSY, -ENOMEM) is better. >> >> --- >> drivers/clk/sunxi/Makefile | 1 + >> drivers/clk/sunxi/clk-sun8i-apb0.c | 80 ++++++++++++++++++++++++++++++++------ >> 2 files changed, 69 insertions(+), 12 deletions(-) >> >> diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile >> index 103efab05ca8..ccf21ba3b6b0 100644 >> --- a/drivers/clk/sunxi/Makefile >> +++ b/drivers/clk/sunxi/Makefile >> @@ -15,6 +15,7 @@ obj-y += clk-sun9i-core.o >> obj-y += clk-sun9i-mmc.o >> obj-y += clk-usb.o >> >> +obj-$(CONFIG_MACH_SUN9I) += clk-sun8i-apb0.o >> obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-cpus.o >> >> obj-$(CONFIG_MFD_SUN6I_PRCM) += \ >> diff --git a/drivers/clk/sunxi/clk-sun8i-apb0.c b/drivers/clk/sunxi/clk-sun8i-apb0.c >> index 7ae5d2c2cde1..7ba61103a6f5 100644 >> --- a/drivers/clk/sunxi/clk-sun8i-apb0.c >> +++ b/drivers/clk/sunxi/clk-sun8i-apb0.c >> @@ -17,13 +17,77 @@ >> #include <linux/clk-provider.h> >> #include <linux/module.h> >> #include <linux/of.h> >> +#include <linux/of_address.h> >> #include <linux/platform_device.h> >> >> +static struct clk *sun8i_a23_apb0_register(struct device_node *node, >> + void __iomem *reg) >> +{ >> + const char *clk_name = node->name; >> + const char *clk_parent; >> + struct clk *clk; >> + int ret; >> + >> + clk_parent = of_clk_get_parent_name(node, 0); >> + if (!clk_parent) >> + return ERR_PTR(-EINVAL); >> + >> + of_property_read_string(node, "clock-output-names", &clk_name); >> + >> + /* The A23 APB0 clock is a standard 2 bit wide divider clock */ >> + clk = clk_register_divider(NULL, clk_name, clk_parent, 0, reg, >> + 0, 2, CLK_DIVIDER_POWER_OF_TWO, NULL); >> + if (IS_ERR(clk)) >> + return clk; >> + >> + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk); >> + if (ret) >> + goto err_unregister; >> + >> + return clk; >> + >> +err_unregister: >> + clk_unregister_divider(clk); >> + >> + return ERR_PTR(ret); >> +} >> + >> +static void sun8i_a23_apb0_setup(struct device_node *node) >> +{ >> + void __iomem *reg; >> + struct resource res; >> + struct clk *clk; >> + >> + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); >> + if (IS_ERR(reg)) { >> + /* >> + * This happens with clk nodes instantiated through mfd, >> + * as those do not have their resources assigned in the >> + * device tree. Do not print an error in this case. >> + */ >> + if (PTR_ERR(reg) != -EINVAL) >> + pr_err("Could not get registers for a23-apb0-clk\n"); > > This is not the only case you have to take into account. > > There's also the case when you have a regular clock (and by regular I > mean that is not in the PRCM) that will be probed by the > CLK_OF_DECLARE mechanism and then later by the device model. > > In such a case, the second of_io_request_and_map will fail, and you > will have an error returned that you do not ignore at the moment. Right. It will return -EBUSY. But ignoring it and returning 0 is telling the driver core that the device successfully binded. I think this is wrong. Normal clocks should be in the "clocks" node, and wouldn't be probed a second time through the device model, would it? Am I missing something? ChenYu
On Mon, Dec 07, 2015 at 09:46:24PM +0800, Chen-Yu Tsai wrote: > On Mon, Dec 7, 2015 at 5:36 PM, Maxime Ripard > <maxime.ripard@free-electrons.com> wrote: > > Hi, > > > > On Thu, Dec 03, 2015 at 03:05:30PM +0800, Chen-Yu Tsai wrote: > >> The APBS clock on sun9i is the same as the APB0 clock on sun8i. With > >> sun9i we are supporting the PRCM clocks by using CLK_OF_DECLARE, > >> instead of through a PRCM mfd device and subdevices for each clock > >> and reset control. As such we need a CLK_OF_DECLARE version of > >> the sun8i-a23-apb0-clk driver. > >> > >> Also, build it for sun9i/A80, and not just for configurations with > >> MFD_SUN6I_PRCM enabled. > >> > >> Signed-off-by: Chen-Yu Tsai <wens@csie.org> > >> --- > >> > >> Changes since v4: > >> > >> - Keep building clk-sun8i-apb0 for SUN6I_MFD_PRCM. > >> > >> - Add an error message and comment for when of_io_request_and_map() > >> fails. of_io_request_and_map() merges a bunch of errors into -EINVAL, > >> so this might not be the best approach. But I think having an error > >> message when we know something is wrong (-EBUSY, -ENOMEM) is better. > >> > >> --- > >> drivers/clk/sunxi/Makefile | 1 + > >> drivers/clk/sunxi/clk-sun8i-apb0.c | 80 ++++++++++++++++++++++++++++++++------ > >> 2 files changed, 69 insertions(+), 12 deletions(-) > >> > >> diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile > >> index 103efab05ca8..ccf21ba3b6b0 100644 > >> --- a/drivers/clk/sunxi/Makefile > >> +++ b/drivers/clk/sunxi/Makefile > >> @@ -15,6 +15,7 @@ obj-y += clk-sun9i-core.o > >> obj-y += clk-sun9i-mmc.o > >> obj-y += clk-usb.o > >> > >> +obj-$(CONFIG_MACH_SUN9I) += clk-sun8i-apb0.o > >> obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-cpus.o > >> > >> obj-$(CONFIG_MFD_SUN6I_PRCM) += \ > >> diff --git a/drivers/clk/sunxi/clk-sun8i-apb0.c b/drivers/clk/sunxi/clk-sun8i-apb0.c > >> index 7ae5d2c2cde1..7ba61103a6f5 100644 > >> --- a/drivers/clk/sunxi/clk-sun8i-apb0.c > >> +++ b/drivers/clk/sunxi/clk-sun8i-apb0.c > >> @@ -17,13 +17,77 @@ > >> #include <linux/clk-provider.h> > >> #include <linux/module.h> > >> #include <linux/of.h> > >> +#include <linux/of_address.h> > >> #include <linux/platform_device.h> > >> > >> +static struct clk *sun8i_a23_apb0_register(struct device_node *node, > >> + void __iomem *reg) > >> +{ > >> + const char *clk_name = node->name; > >> + const char *clk_parent; > >> + struct clk *clk; > >> + int ret; > >> + > >> + clk_parent = of_clk_get_parent_name(node, 0); > >> + if (!clk_parent) > >> + return ERR_PTR(-EINVAL); > >> + > >> + of_property_read_string(node, "clock-output-names", &clk_name); > >> + > >> + /* The A23 APB0 clock is a standard 2 bit wide divider clock */ > >> + clk = clk_register_divider(NULL, clk_name, clk_parent, 0, reg, > >> + 0, 2, CLK_DIVIDER_POWER_OF_TWO, NULL); > >> + if (IS_ERR(clk)) > >> + return clk; > >> + > >> + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk); > >> + if (ret) > >> + goto err_unregister; > >> + > >> + return clk; > >> + > >> +err_unregister: > >> + clk_unregister_divider(clk); > >> + > >> + return ERR_PTR(ret); > >> +} > >> + > >> +static void sun8i_a23_apb0_setup(struct device_node *node) > >> +{ > >> + void __iomem *reg; > >> + struct resource res; > >> + struct clk *clk; > >> + > >> + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); > >> + if (IS_ERR(reg)) { > >> + /* > >> + * This happens with clk nodes instantiated through mfd, > >> + * as those do not have their resources assigned in the > >> + * device tree. Do not print an error in this case. > >> + */ > >> + if (PTR_ERR(reg) != -EINVAL) > >> + pr_err("Could not get registers for a23-apb0-clk\n"); > > > > This is not the only case you have to take into account. > > > > There's also the case when you have a regular clock (and by regular I > > mean that is not in the PRCM) that will be probed by the > > CLK_OF_DECLARE mechanism and then later by the device model. > > > > In such a case, the second of_io_request_and_map will fail, and you > > will have an error returned that you do not ignore at the moment. > > Right. It will return -EBUSY. But ignoring it and returning 0 is telling > the driver core that the device successfully binded. I think this is > wrong. Well, technically, it is already bound. > Normal clocks should be in the "clocks" node, and wouldn't be probed a > second time through the device model, would it? Am I missing something? Hmmm, that's true. Maxime
On Thu, Dec 03, 2015 at 03:05:30PM +0800, Chen-Yu Tsai wrote: > The APBS clock on sun9i is the same as the APB0 clock on sun8i. With > sun9i we are supporting the PRCM clocks by using CLK_OF_DECLARE, > instead of through a PRCM mfd device and subdevices for each clock > and reset control. As such we need a CLK_OF_DECLARE version of > the sun8i-a23-apb0-clk driver. > > Also, build it for sun9i/A80, and not just for configurations with > MFD_SUN6I_PRCM enabled. > > Signed-off-by: Chen-Yu Tsai <wens@csie.org> Applied, thanks! Maxime
diff --git a/drivers/clk/sunxi/Makefile b/drivers/clk/sunxi/Makefile index 103efab05ca8..ccf21ba3b6b0 100644 --- a/drivers/clk/sunxi/Makefile +++ b/drivers/clk/sunxi/Makefile @@ -15,6 +15,7 @@ obj-y += clk-sun9i-core.o obj-y += clk-sun9i-mmc.o obj-y += clk-usb.o +obj-$(CONFIG_MACH_SUN9I) += clk-sun8i-apb0.o obj-$(CONFIG_MACH_SUN9I) += clk-sun9i-cpus.o obj-$(CONFIG_MFD_SUN6I_PRCM) += \ diff --git a/drivers/clk/sunxi/clk-sun8i-apb0.c b/drivers/clk/sunxi/clk-sun8i-apb0.c index 7ae5d2c2cde1..7ba61103a6f5 100644 --- a/drivers/clk/sunxi/clk-sun8i-apb0.c +++ b/drivers/clk/sunxi/clk-sun8i-apb0.c @@ -17,13 +17,77 @@ #include <linux/clk-provider.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_address.h> #include <linux/platform_device.h> +static struct clk *sun8i_a23_apb0_register(struct device_node *node, + void __iomem *reg) +{ + const char *clk_name = node->name; + const char *clk_parent; + struct clk *clk; + int ret; + + clk_parent = of_clk_get_parent_name(node, 0); + if (!clk_parent) + return ERR_PTR(-EINVAL); + + of_property_read_string(node, "clock-output-names", &clk_name); + + /* The A23 APB0 clock is a standard 2 bit wide divider clock */ + clk = clk_register_divider(NULL, clk_name, clk_parent, 0, reg, + 0, 2, CLK_DIVIDER_POWER_OF_TWO, NULL); + if (IS_ERR(clk)) + return clk; + + ret = of_clk_add_provider(node, of_clk_src_simple_get, clk); + if (ret) + goto err_unregister; + + return clk; + +err_unregister: + clk_unregister_divider(clk); + + return ERR_PTR(ret); +} + +static void sun8i_a23_apb0_setup(struct device_node *node) +{ + void __iomem *reg; + struct resource res; + struct clk *clk; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(reg)) { + /* + * This happens with clk nodes instantiated through mfd, + * as those do not have their resources assigned in the + * device tree. Do not print an error in this case. + */ + if (PTR_ERR(reg) != -EINVAL) + pr_err("Could not get registers for a23-apb0-clk\n"); + + return; + } + + clk = sun8i_a23_apb0_register(node, reg); + if (IS_ERR(clk)) + goto err_unmap; + + return; + +err_unmap: + iounmap(reg); + of_address_to_resource(node, 0, &res); + release_mem_region(res.start, resource_size(&res)); +} +CLK_OF_DECLARE(sun8i_a23_apb0, "allwinner,sun8i-a23-apb0-clk", + sun8i_a23_apb0_setup); + static int sun8i_a23_apb0_clk_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; - const char *clk_name = np->name; - const char *clk_parent; struct resource *r; void __iomem *reg; struct clk *clk; @@ -33,19 +97,11 @@ static int sun8i_a23_apb0_clk_probe(struct platform_device *pdev) if (IS_ERR(reg)) return PTR_ERR(reg); - clk_parent = of_clk_get_parent_name(np, 0); - if (!clk_parent) - return -EINVAL; - - of_property_read_string(np, "clock-output-names", &clk_name); - - /* The A23 APB0 clock is a standard 2 bit wide divider clock */ - clk = clk_register_divider(&pdev->dev, clk_name, clk_parent, 0, reg, - 0, 2, CLK_DIVIDER_POWER_OF_TWO, NULL); + clk = sun8i_a23_apb0_register(np, reg); if (IS_ERR(clk)) return PTR_ERR(clk); - return of_clk_add_provider(np, of_clk_src_simple_get, clk); + return 0; } static const struct of_device_id sun8i_a23_apb0_clk_dt_ids[] = {
The APBS clock on sun9i is the same as the APB0 clock on sun8i. With sun9i we are supporting the PRCM clocks by using CLK_OF_DECLARE, instead of through a PRCM mfd device and subdevices for each clock and reset control. As such we need a CLK_OF_DECLARE version of the sun8i-a23-apb0-clk driver. Also, build it for sun9i/A80, and not just for configurations with MFD_SUN6I_PRCM enabled. Signed-off-by: Chen-Yu Tsai <wens@csie.org> --- Changes since v4: - Keep building clk-sun8i-apb0 for SUN6I_MFD_PRCM. - Add an error message and comment for when of_io_request_and_map() fails. of_io_request_and_map() merges a bunch of errors into -EINVAL, so this might not be the best approach. But I think having an error message when we know something is wrong (-EBUSY, -ENOMEM) is better. --- drivers/clk/sunxi/Makefile | 1 + drivers/clk/sunxi/clk-sun8i-apb0.c | 80 ++++++++++++++++++++++++++++++++------ 2 files changed, 69 insertions(+), 12 deletions(-)