From 62c83cde9282a9580994a12b3063e677181b5ebe Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:13 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: whitespace pre-clean GPIO SUPPORT FOR SCx200 & PC8736x The patch-set reworks the 2.4 vintage scx200_gpio driver for modern 2.6, and refactors GPIO support to reuse it in a new driver for the GPIO on PC-8736x chips. Its handy for the Soekris.com net-4801, which has both chips. These patches have been seen recently on Kernel-Mentors, and then Kernel-Newbies ML, where Jesper Juhl kindly reviewed it. His feedback has been incorporated. Thanks Jesper ! Its also gone to soekris-tech@soekris.com for possible testing by linux folks, I've gotten 1 promise so far. Theyre mostly BSD folk over there, but we'll see.. Device-file & Sysfs The driver preserves the existing device-file interface, including the write/cmd set, but adds v to 'view' the pin-settings & configs by inducing, via gpio_dump(), a dev_info() call. Its a fairly crappy way to get status, but it sticks to the syslog approach, conservatively. Allowing users to voluntarily trigger logging is good, it gives them a familiar way to confirm their app's control & use of the pins, and I've thus reduced the pin-mode-updates from dev_info to dev_dbg. I've recently bolted on a proto sysfs interface for both new drivers. Im not including those patches here; they (the patch + doc-pre-patch) are still quite raw (and unreviewed on KNML), and since they 'invent' a convention for GPIO, a proper vetting is needed. Since this patchset is much bigger than my previous ones, Id like to keep things simpler, and address it 1st, before bolting on more stuff. The driver-split The Geode CPU and the PC-87366 Super-IO chip have GPIO units which share a common pin-architecture (same pin features, with same bits controlling), but with different addressing mechanics and port organizations. The vintage driver expresses the pin capabilities with pin-mode commands [OoPpTt],etc that change the pin configurations, and since the 2 chips share pin-arch, we can reuse the read(), write() commands, once the implementation is suitably adjusted. The patchset adds a vtable: struct nsc_gpio_ops, to abstract the existing gpio operations, then adjusts fileops.write() code to invoke operations via that vtable. Driver specific open()s set private_data to the vtable so its available for use by write(). The vtable gets the gpio_dump() too, since its user-friendly, and (could be construed as) part of the current device-file interface. To support use of dev_dbg() in write() & _dump(), the vtable gets a dev ptr too, set by both scx200 & pc8736x _gpio drivers. heres how the pins are presented in syslog: [ 1890.176223] scx200_gpio.0: io00: 0x0044 TS OD PUE EDGE LO DEBOUNCE [ 1890.287223] scx200_gpio.0: io01: 0x0003 OE PP PUD EDGE LO nsc_gpio.c: new file is new home of several file-ops methods, which are modified to get their vtable from filp->private_data, and use it where needed. scx200_gpio.c: keeps some of its existing gpio routines, but now wires them up via the vtable (they're invoked by nsc_gpio.c:nsc_gpio_write() thru this vtable). A driver-spcific open() initializes filp->private_data with the vtable. Once the split is clean, and the scx200_gpio driver is working, we copy and modify the function and variable names, and rework the access-method bodies for the different addressing scheme. Heres a working overview of the patchset: # series file for GPIO # Spring Cleaning gpio-scx/patch.preclean # scripts/Lindent fixes, editor-ctrl comments # API Modernization gpio-scx/patch.api26 # what I learned from LDD3 gpio-scx/patch.platform-dev-2 # get pdev, support for dev_dbg() gpio-scx/patch.unsigned-minor # fix to match std practice # Debuggability gpio-scx/patch.dump-diet # shrink gpio_dump() gpio-scx/patch.viewpins # add new 'command' to call dump() gpio-scx/patch.init-refactor # pull shadow-register init to sub # Access-Abstraction (add vtable) gpio-scx/patch.access-vtable # introduce nsg_gpio_ops vtable, w dump gpio-scx/patch.vtable-calls # add & use the vtable in scx200_gpio gpio-scx/patch.nscgpio-shell # add empty driver for common-fops # move code under abstraction gpio-scx/patch.migrate-fops # move file-ops methods from scx200_gpio gpio-scx/patch.common-dump # mv scx200.c:scx200_gpio_dump() to nsc_gpio.c gpio-scx/patch.add-pc8736x-gpio # add new driver, like old, w chip adapt # gpio-scx/patch.add-DEBUG # enable all dev_dbg()s # Cleanups # finish printk -> dev_dbg() etc gpio-scx/patch.pdev-pc8736x # new drvr needs pdev too, gpio-scx/patch.devdbg-nscgpio # add device to 'vtable', use in dev_dbg() # gpio-scx/patch.pin-config-view # another 'c' 'command' # gpio-scx/quiet-getset # take out excess dbg stuff (pretty quiet now) gpio-scx/patch.shadow-current # imitate scx200_gpio's shadow regs in pc87* # post KMentors-post patches .. gpio-scx/patch.mutexes # use mutexes for config-locks gpio-scx/patch.viewpins-values # extend dump to obsolete separate 'c' cmd gpio-scx/patch.kconfig # add stuff for kbuild # TBC # combine api26 with pdev, which is just one step. # merge c&v commands to single do-all-fn # delay viewpins, dump-diet should also un-ifdef it too. diff.sys-gpio-rollup-1 This patch: Removed editor format-control comments, and used scripts/Lindent to clean up whitespace, then deleted the bogus chunks :-( Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 7 ------- 1 file changed, 7 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 321f5fd26e75..4d3d8e811fe1 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -159,10 +159,3 @@ EXPORT_SYMBOL(scx200_gpio_base); EXPORT_SYMBOL(scx200_gpio_shadow); EXPORT_SYMBOL(scx200_gpio_configure); EXPORT_SYMBOL(scx200_cb_base); - -/* - Local variables: - compile-command: "make -k -C ../../.. SUBDIRS=arch/i386/kernel modules" - c-basic-offset: 8 - End: -*/ -- cgit v1.2.3 From 55b8c0455b8aeb80f94183fa3aa42e3fa62b1705 Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:15 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: device minor numbers are unsigned ints Per kernel headers, device minor numbers are unsigned ints. Do the same in this driver. Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 4d3d8e811fe1..18f895ce2488 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -87,7 +87,7 @@ static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_ return 0; } -u32 scx200_gpio_configure(int index, u32 mask, u32 bits) +u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) { u32 config, new_config; unsigned long flags; -- cgit v1.2.3 From d424aa8744b7b7db1d32476ae6c8015d10eebe1c Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:16 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: put gpio_dump on a diet Shrink scx200_gpio_dump() to a single printk with ternary ops. The function is still ifdef'd out, this is corrected in next patch, when it is actually used. The patch 'inadvertently' changed loglevel from DEBUG to INFO. This is Good, because in next patch, its wired to a 'command' which the user can invoke when they want. When they do so, its because they want INFO to support their developement effort, and we want to give it to them without compiling a DEBUG version of the driver. Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 39 +++++++++++---------------------------- 1 file changed, 11 insertions(+), 28 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 18f895ce2488..9e96a785dd05 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -108,34 +108,17 @@ u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) #if 0 void scx200_gpio_dump(unsigned index) { - u32 config = scx200_gpio_configure(index, ~0, 0); - printk(KERN_DEBUG "GPIO%02u: 0x%08lx", index, (unsigned long)config); - - if (config & 1) - printk(" OE"); /* output enabled */ - else - printk(" TS"); /* tristate */ - if (config & 2) - printk(" PP"); /* push pull */ - else - printk(" OD"); /* open drain */ - if (config & 4) - printk(" PUE"); /* pull up enabled */ - else - printk(" PUD"); /* pull up disabled */ - if (config & 8) - printk(" LOCKED"); /* locked */ - if (config & 16) - printk(" LEVEL"); /* level input */ - else - printk(" EDGE"); /* edge input */ - if (config & 32) - printk(" HI"); /* trigger on rising edge */ - else - printk(" LO"); /* trigger on falling edge */ - if (config & 64) - printk(" DEBOUNCE"); /* debounce */ - printk("\n"); + u32 config = scx200_gpio_configure(index, ~0, 0); + + printk(KERN_INFO NAME ": GPIO-%02u: 0x%08lx %s %s %s %s %s %s %s\n", + index, (unsigned long) config, + (config & 1) ? "OE" : "TS", /* output enabled / tristate */ + (config & 2) ? "PP" : "OD", /* push pull / open drain */ + (config & 4) ? "PUE" : "PUD", /* pull up enabled/disabled */ + (config & 8) ? "LOCKED" : "", /* locked / unlocked */ + (config & 16) ? "LEVEL" : "EDGE", /* level/edge input */ + (config & 32) ? "HI" : "LO", /* trigger on rising/falling edge */ + (config & 64) ? "DEBOUNCE" : ""); /* debounce */ } #endif /* 0 */ -- cgit v1.2.3 From 9550a339e1ab1709dd53d92a1b76eecae2df9f3c Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:16 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: add 'v' command to device-file Add a new driver command: 'v' which calls gpio_dump() on the pin. The output goes to the log, like all other INFO messages in the original driver. Giving the user control over the feedback they 'need' is construed to be a user-friendly feature, and allows us (later) to dial down many INFO messages to DEBUG log-level. Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 9e96a785dd05..009e6aa16f73 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -105,7 +105,6 @@ u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) return config; } -#if 0 void scx200_gpio_dump(unsigned index) { u32 config = scx200_gpio_configure(index, ~0, 0); @@ -120,7 +119,6 @@ void scx200_gpio_dump(unsigned index) (config & 32) ? "HI" : "LO", /* trigger on rising/falling edge */ (config & 64) ? "DEBOUNCE" : ""); /* debounce */ } -#endif /* 0 */ static int __init scx200_init(void) { @@ -141,4 +139,5 @@ module_exit(scx200_cleanup); EXPORT_SYMBOL(scx200_gpio_base); EXPORT_SYMBOL(scx200_gpio_shadow); EXPORT_SYMBOL(scx200_gpio_configure); +EXPORT_SYMBOL(scx200_gpio_dump); EXPORT_SYMBOL(scx200_cb_base); -- cgit v1.2.3 From 9b170b8fdbd14a197ad26b4354f3810c65a96602 Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:17 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: refactor scx200_probe to better segregate _gpio initialization Pull shadow-reg initialization into separate function now, rather than doing it 2x later (scx200, pc8736x). When we revisit 2nd drvr below, it will be to reimplement an init function, rather than another refactor. Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 009e6aa16f73..27be55349c65 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -47,9 +47,17 @@ static struct pci_driver scx200_pci_driver = { static DEFINE_SPINLOCK(scx200_gpio_config_lock); -static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +static void __devinit scx200_init_shadow(void) { int bank; + + /* read the current values driven on the GPIO signals */ + for (bank = 0; bank < 2; ++bank) + scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank); +} + +static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +{ unsigned base; if (pdev->device == PCI_DEVICE_ID_NS_SCx200_BRIDGE || @@ -63,10 +71,7 @@ static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_ } scx200_gpio_base = base; - - /* read the current values driven on the GPIO signals */ - for (bank = 0; bank < 2; ++bank) - scx200_gpio_shadow[bank] = inl(scx200_gpio_base + 0x10 * bank); + scx200_init_shadow(); } else { /* find the base of the Configuration Block */ -- cgit v1.2.3 From 0e41ef3c51ea7dbb764616f60a90700647fc8518 Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:20 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: migrate gpio_dump to common module Since the meaning of config-bits is the same for scx200 and pc8736x _gpios, we can share a function to deliver this to user. Since it is called via the vtable, its also completely replaceable. For now, we keep using printk... Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 16 ---------------- 1 file changed, 16 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index 27be55349c65..edead73ebef2 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -110,21 +110,6 @@ u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) return config; } -void scx200_gpio_dump(unsigned index) -{ - u32 config = scx200_gpio_configure(index, ~0, 0); - - printk(KERN_INFO NAME ": GPIO-%02u: 0x%08lx %s %s %s %s %s %s %s\n", - index, (unsigned long) config, - (config & 1) ? "OE" : "TS", /* output enabled / tristate */ - (config & 2) ? "PP" : "OD", /* push pull / open drain */ - (config & 4) ? "PUE" : "PUD", /* pull up enabled/disabled */ - (config & 8) ? "LOCKED" : "", /* locked / unlocked */ - (config & 16) ? "LEVEL" : "EDGE", /* level/edge input */ - (config & 32) ? "HI" : "LO", /* trigger on rising/falling edge */ - (config & 64) ? "DEBOUNCE" : ""); /* debounce */ -} - static int __init scx200_init(void) { printk(KERN_INFO NAME ": NatSemi SCx200 Driver\n"); @@ -144,5 +129,4 @@ module_exit(scx200_cleanup); EXPORT_SYMBOL(scx200_gpio_base); EXPORT_SYMBOL(scx200_gpio_shadow); EXPORT_SYMBOL(scx200_gpio_configure); -EXPORT_SYMBOL(scx200_gpio_dump); EXPORT_SYMBOL(scx200_cb_base); -- cgit v1.2.3 From 8bcf6135c3e8cdfab375f4041a48721483519eee Mon Sep 17 00:00:00 2001 From: Jim Cromie Date: Tue, 27 Jun 2006 02:54:25 -0700 Subject: [PATCH] chardev: GPIO for SCx200 & PC-8736x: replace spinlocks w mutexes Replace spinlocks guarding gpio config ops with mutexes. This is a me-too patch, and is justifiable insofar as mutexes have stricter semantics and better debugging support, so are preferred where they are applicable. Signed-off-by: Jim Cromie Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/i386/kernel/scx200.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/i386/kernel/scx200.c') diff --git a/arch/i386/kernel/scx200.c b/arch/i386/kernel/scx200.c index edead73ebef2..9bf590cefc7d 100644 --- a/arch/i386/kernel/scx200.c +++ b/arch/i386/kernel/scx200.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -45,7 +46,7 @@ static struct pci_driver scx200_pci_driver = { .probe = scx200_probe, }; -static DEFINE_SPINLOCK(scx200_gpio_config_lock); +static DEFINE_MUTEX(scx200_gpio_config_lock); static void __devinit scx200_init_shadow(void) { @@ -95,9 +96,8 @@ static int __devinit scx200_probe(struct pci_dev *pdev, const struct pci_device_ u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) { u32 config, new_config; - unsigned long flags; - spin_lock_irqsave(&scx200_gpio_config_lock, flags); + mutex_lock(&scx200_gpio_config_lock); outl(index, scx200_gpio_base + 0x20); config = inl(scx200_gpio_base + 0x24); @@ -105,7 +105,7 @@ u32 scx200_gpio_configure(unsigned index, u32 mask, u32 bits) new_config = (config & mask) | bits; outl(new_config, scx200_gpio_base + 0x24); - spin_unlock_irqrestore(&scx200_gpio_config_lock, flags); + mutex_unlock(&scx200_gpio_config_lock); return config; } -- cgit v1.2.3