| Message ID | 1498664922-28493-10-git-send-email-aleksandar.markovic@rt-rk.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jun 28, 2017 at 05:47:02PM +0200, Aleksandar Markovic wrote: > From: Miodrag Dinic <miodrag.dinic@imgtec.com> > > ARCH_MIGHT_HAVE_PC_SERIO is selected by default for MIPS platforms. > As a consequence SERIO_I8042 would be automatically selected for any > MIPS board which wants to enable input support like keyboard > (INPUT_KEYBOARD) regardless of i8042 controller existence. > > The dependency is as follows : > > config ARCH_MIGHT_HAVE_PC_SERIO [=y] > Defined at drivers/input/serio/Kconfig:19 > Depends on: !UML > Selected by: MIPS [=y] > > config SERIO > Defined at drivers/input/serio/Kconfig:4 > default y > Depends on: !UML > Selected by: KEYBOARD_ATKBD [=y] && !UML && INPUT [=y] && > INPUT_KEYBOARD [=y] > > config SERIO_I8042 > Defined at drivers/input/serio/Kconfig:28 > tristate "i8042 PC Keyboard controller" > default y > Depends on: !UML && SERIO [=y] && ARCH_MIGHT_HAVE_PC_SERIO [=y] > Selected by: KEYBOARD_ATKBD [=y] && !UML && INPUT [=y] && > INPUT_KEYBOARD [=y] && ARCH_MIGHT_HAVE_PC_SERIO [=y] > > If this driver probes the I8042_DATA_REG not knowing if the device > exists it can cause a kernel to crash. Using check_legacy_ioport() > interface we can selectively enable this driver only for the MIPS > boards which actually have the i8042 controller. > > New "Ranchu" virtual platform does not support i8042 controller > so it's added to the blacklist match table. > > Each MIPS machine should update this table with it's compatible strings > if it does not support i8042 controller. > > In order to utilize this mechanism, each MIPS machine that do not > have i8042 controller should update the blacklist table with its > compatible strings. > > Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> > Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> > Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> > --- > arch/mips/kernel/setup.c | 16 ++++++++++++++++ > drivers/input/serio/i8042-io.h | 2 +- > 2 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c > index c22cde8..c3e0d2b 100644 > --- a/arch/mips/kernel/setup.c > +++ b/arch/mips/kernel/setup.c > @@ -79,6 +79,15 @@ const unsigned long mips_io_port_base = -1; > EXPORT_SYMBOL(mips_io_port_base); > > /* > + * Here we blacklist all MIPS boards which do not have i8042 controller > + */ > +static const struct of_device_id i8042_blacklist_of_match[] = { > + { .compatible = "mti,ranchu", }, > + {}, > +}; > +#define I8042_DATA_REG 0x60 > + > +/* > * Check for existence of legacy devices > * > * Some drivers may try to probe some I/O ports which can lead to > @@ -90,9 +99,16 @@ EXPORT_SYMBOL(mips_io_port_base); > */ > int check_legacy_ioport(unsigned long base_port) > { > + struct device_node *np; > int ret = 0; > > switch (base_port) { > + case I8042_DATA_REG: > + np = of_find_matching_node(NULL, i8042_blacklist_of_match); > + if (np) > + ret = -ENODEV; > + of_node_put(np); > + break; Can you simply mark 8042 region as busy when you are setting up the board, so when i8042 tries to requets it it will fail? > default: > /* We will assume that the I/O device port exists if > * not explicitly added to the blacklist match table > diff --git a/drivers/input/serio/i8042-io.h b/drivers/input/serio/i8042-io.h > index 34da81c..ec5fe9e 100644 > --- a/drivers/input/serio/i8042-io.h > +++ b/drivers/input/serio/i8042-io.h > @@ -72,7 +72,7 @@ static inline int i8042_platform_init(void) > * On some platforms touching the i8042 data register region can do really > * bad things. Because of this the region is always reserved on such boxes. > */ > -#if defined(CONFIG_PPC) > +#if defined(CONFIG_PPC) || defined(CONFIG_MIPS) > if (check_legacy_ioport(I8042_DATA_REG)) > return -ENODEV; > #endif > -- > 2.7.4 > Thanks.
Hi, On 28 June 2017 at 17:47, Aleksandar Markovic <aleksandar.markovic@rt-rk.com> wrote: > From: Miodrag Dinic <miodrag.dinic@imgtec.com> > > ARCH_MIGHT_HAVE_PC_SERIO is selected by default for MIPS platforms. > As a consequence SERIO_I8042 would be automatically selected for any > MIPS board which wants to enable input support like keyboard > (INPUT_KEYBOARD) regardless of i8042 controller existence. > > The dependency is as follows : > > config ARCH_MIGHT_HAVE_PC_SERIO [=y] > Defined at drivers/input/serio/Kconfig:19 > Depends on: !UML > Selected by: MIPS [=y] > > config SERIO > Defined at drivers/input/serio/Kconfig:4 > default y > Depends on: !UML > Selected by: KEYBOARD_ATKBD [=y] && !UML && INPUT [=y] && > INPUT_KEYBOARD [=y] > > config SERIO_I8042 > Defined at drivers/input/serio/Kconfig:28 > tristate "i8042 PC Keyboard controller" > default y > Depends on: !UML && SERIO [=y] && ARCH_MIGHT_HAVE_PC_SERIO [=y] > Selected by: KEYBOARD_ATKBD [=y] && !UML && INPUT [=y] && > INPUT_KEYBOARD [=y] && ARCH_MIGHT_HAVE_PC_SERIO [=y] > > If this driver probes the I8042_DATA_REG not knowing if the device > exists it can cause a kernel to crash. Using check_legacy_ioport() > interface we can selectively enable this driver only for the MIPS > boards which actually have the i8042 controller. > > New "Ranchu" virtual platform does not support i8042 controller > so it's added to the blacklist match table. > > Each MIPS machine should update this table with it's compatible strings > if it does not support i8042 controller. > > In order to utilize this mechanism, each MIPS machine that do not > have i8042 controller should update the blacklist table with its > compatible strings. > > Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com> > Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com> > Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com> > --- > arch/mips/kernel/setup.c | 16 ++++++++++++++++ > drivers/input/serio/i8042-io.h | 2 +- > 2 files changed, 17 insertions(+), 1 deletion(-) > > diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c > index c22cde8..c3e0d2b 100644 > --- a/arch/mips/kernel/setup.c > +++ b/arch/mips/kernel/setup.c > @@ -79,6 +79,15 @@ const unsigned long mips_io_port_base = -1; > EXPORT_SYMBOL(mips_io_port_base); > > /* > + * Here we blacklist all MIPS boards which do not have i8042 controller > + */ > +static const struct of_device_id i8042_blacklist_of_match[] = { > + { .compatible = "mti,ranchu", }, > + {}, > +}; > +#define I8042_DATA_REG 0x60 > + > +/* > * Check for existence of legacy devices > * > * Some drivers may try to probe some I/O ports which can lead to > @@ -90,9 +99,16 @@ EXPORT_SYMBOL(mips_io_port_base); > */ > int check_legacy_ioport(unsigned long base_port) > { > + struct device_node *np; > int ret = 0; > > switch (base_port) { > + case I8042_DATA_REG: > + np = of_find_matching_node(NULL, i8042_blacklist_of_match); > + if (np) > + ret = -ENODEV; > + of_node_put(np); > + break; Wouldn't it make more sense to require boards to describe their i8042 device(s) in device tree if USE_OF is enabled? And maybe a whitelist for those preexisting ones that don't. Much less maintenance overhead for new boards, as I suspect the amount of boards with i8042 support is much less than those that don't. At least PowerPC seems to do it this way. Regards Jonas -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index c22cde8..c3e0d2b 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -79,6 +79,15 @@ const unsigned long mips_io_port_base = -1; EXPORT_SYMBOL(mips_io_port_base); /* + * Here we blacklist all MIPS boards which do not have i8042 controller + */ +static const struct of_device_id i8042_blacklist_of_match[] = { + { .compatible = "mti,ranchu", }, + {}, +}; +#define I8042_DATA_REG 0x60 + +/* * Check for existence of legacy devices * * Some drivers may try to probe some I/O ports which can lead to @@ -90,9 +99,16 @@ EXPORT_SYMBOL(mips_io_port_base); */ int check_legacy_ioport(unsigned long base_port) { + struct device_node *np; int ret = 0; switch (base_port) { + case I8042_DATA_REG: + np = of_find_matching_node(NULL, i8042_blacklist_of_match); + if (np) + ret = -ENODEV; + of_node_put(np); + break; default: /* We will assume that the I/O device port exists if * not explicitly added to the blacklist match table diff --git a/drivers/input/serio/i8042-io.h b/drivers/input/serio/i8042-io.h index 34da81c..ec5fe9e 100644 --- a/drivers/input/serio/i8042-io.h +++ b/drivers/input/serio/i8042-io.h @@ -72,7 +72,7 @@ static inline int i8042_platform_init(void) * On some platforms touching the i8042 data register region can do really * bad things. Because of this the region is always reserved on such boxes. */ -#if defined(CONFIG_PPC) +#if defined(CONFIG_PPC) || defined(CONFIG_MIPS) if (check_legacy_ioport(I8042_DATA_REG)) return -ENODEV; #endif