| Message ID | 20190504010030.29233-6-pierre-louis.bossart@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | soundwire: add sysfs and debugfs support | expand |
On Fri, May 03, 2019 at 08:00:28PM -0500, Pierre-Louis Bossart wrote: > Add base debugfs mechanism for SoundWire bus by creating soundwire > root and master-N and slave-x hierarchy. > > Also add SDW Slave SCP, DP0 and DP-N register debug file. > > Registers not implemented will print as "XX" > > Credits: this patch is based on an earlier internal contribution by > Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah. The main change > is the use of scnprintf to avoid known issues with snprintf. > > Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > --- > drivers/soundwire/Makefile | 3 +- > drivers/soundwire/bus.c | 5 + > drivers/soundwire/bus.h | 28 +++++ > drivers/soundwire/bus_type.c | 3 + > drivers/soundwire/debugfs.c | 214 ++++++++++++++++++++++++++++++++++ > drivers/soundwire/slave.c | 1 + > include/linux/soundwire/sdw.h | 9 ++ > 7 files changed, 262 insertions(+), 1 deletion(-) > create mode 100644 drivers/soundwire/debugfs.c > > diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile > index a72a29731a28..f2c425fa15bd 100644 > --- a/drivers/soundwire/Makefile > +++ b/drivers/soundwire/Makefile > @@ -4,7 +4,8 @@ > > #Bus Objs > soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o stream.o \ > - sysfs.o sysfs_slave_dp0.o sysfs_slave_dpn.o > + sysfs.o sysfs_slave_dp0.o sysfs_slave_dpn.o \ > + debugfs.o > obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o > > #Cadence Objs > diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c > index dd9181693554..b79eba321b71 100644 > --- a/drivers/soundwire/bus.c > +++ b/drivers/soundwire/bus.c > @@ -53,6 +53,8 @@ int sdw_add_bus_master(struct sdw_bus *bus) > if (ret < 0) > dev_warn(bus->dev, "Bus sysfs init failed:%d\n", ret); > > + bus->debugfs = sdw_bus_debugfs_init(bus); > + > /* > * Device numbers in SoundWire are 0 through 15. Enumeration device > * number (0), Broadcast device number (15), Group numbers (12 and > @@ -114,6 +116,7 @@ static int sdw_delete_slave(struct device *dev, void *data) > struct sdw_bus *bus = slave->bus; > > sdw_sysfs_slave_exit(slave); > + sdw_slave_debugfs_exit(slave->debugfs); > > mutex_lock(&bus->bus_lock); > > @@ -136,6 +139,8 @@ static int sdw_delete_slave(struct device *dev, void *data) > void sdw_delete_bus_master(struct sdw_bus *bus) > { > sdw_sysfs_bus_exit(bus); > + if (bus->debugfs) > + sdw_bus_debugfs_exit(bus->debugfs); No need to check, just call it. > > device_for_each_child(bus->dev, NULL, sdw_delete_slave); > } > diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h > index 0707e68a8d21..f0b1f4f9d7b2 100644 > --- a/drivers/soundwire/bus.h > +++ b/drivers/soundwire/bus.h > @@ -20,6 +20,34 @@ void sdw_extract_slave_id(struct sdw_bus *bus, > > extern const struct attribute_group *sdw_slave_dev_attr_groups[]; > > +#ifdef CONFIG_DEBUG_FS > +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus); > +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d); > +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d); > +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave); > +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d); > +void sdw_debugfs_init(void); > +void sdw_debugfs_exit(void); > +#else > +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus) > +{ return NULL; } > + > +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d) {} > + > +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) > +{ return NULL; } > + > +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave) > +{ return NULL; } > + > +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d) {} > + > +void sdw_debugfs_init(void) {} > + > +void sdw_debugfs_exit(void) {} > + > +#endif > + > enum { > SDW_MSG_FLAG_READ = 0, > SDW_MSG_FLAG_WRITE, > diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c > index f68fe45c1037..f28c1a2446af 100644 > --- a/drivers/soundwire/bus_type.c > +++ b/drivers/soundwire/bus_type.c > @@ -6,6 +6,7 @@ > #include <linux/pm_domain.h> > #include <linux/soundwire/sdw.h> > #include <linux/soundwire/sdw_type.h> > +#include "bus.h" > > /** > * sdw_get_device_id - find the matching SoundWire device id > @@ -182,11 +183,13 @@ EXPORT_SYMBOL_GPL(sdw_unregister_driver); > > static int __init sdw_bus_init(void) > { > + sdw_debugfs_init(); > return bus_register(&sdw_bus_type); > } > > static void __exit sdw_bus_exit(void) > { > + sdw_debugfs_exit(); > bus_unregister(&sdw_bus_type); > } > > diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c > new file mode 100644 > index 000000000000..8a8b4df95c46 > --- /dev/null > +++ b/drivers/soundwire/debugfs.c > @@ -0,0 +1,214 @@ > +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) > +// Copyright(c) 2017-19 Intel Corporation. > + > +#include <linux/device.h> > +#include <linux/debugfs.h> > +#include <linux/mod_devicetable.h> > +#include <linux/slab.h> > +#include <linux/soundwire/sdw.h> > +#include <linux/soundwire/sdw_registers.h> > +#include "bus.h" > + > +#ifdef CONFIG_DEBUG_FS > +struct dentry *sdw_debugfs_root; > +#endif > + > +struct sdw_bus_debugfs { > + struct sdw_bus *bus; Why do you need to save this pointer? > + struct dentry *fs; This really is all you need to have around, right? > +}; > + > +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus) > +{ > + struct sdw_bus_debugfs *d; > + char name[16]; > + > + if (!sdw_debugfs_root) > + return NULL; > + > + d = kzalloc(sizeof(*d), GFP_KERNEL); > + if (!d) > + return NULL; > + > + /* create the debugfs master-N */ > + snprintf(name, sizeof(name), "master-%d", bus->link_id); > + d->fs = debugfs_create_dir(name, sdw_debugfs_root); > + if (IS_ERR_OR_NULL(d->fs)) { > + dev_err(bus->dev, "debugfs root creation failed\n"); > + goto err; > + } > + > + d->bus = bus; > + > + return d; > + > +err: > + kfree(d); > + return NULL; > +} > + > +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d) > +{ > + debugfs_remove_recursive(d->fs); > + kfree(d); > +} > + > +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) > +{ > + if (d) > + return d->fs; > + return NULL; > +} > +EXPORT_SYMBOL(sdw_bus_debugfs_get_root); _GPL()? But why is this exported at all? No one calls this function. > +struct sdw_slave_debugfs { > + struct sdw_slave *slave; Same question as above, why do you need this pointer? And meta-comment, if you _EVER_ save off a pointer to a reference counted object (like this and the above one), you HAVE to grab a reference to it, otherwise it can go away at any point in time as that is the point of reference counted objects. So even if you do need/want this, you have to properly handle the reference count by incrementing/decrementing it as needed. > + > + struct dentry *fs; > +}; > + > +#define RD_BUF (3 * PAGE_SIZE) > + > +static ssize_t sdw_sprintf(struct sdw_slave *slave, > + char *buf, size_t pos, unsigned int reg) > +{ > + int value; > + > + value = sdw_read(slave, reg); > + > + if (value < 0) > + return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg); > + else > + return scnprintf(buf + pos, RD_BUF - pos, > + "%3x\t%2x\n", reg, value); > +} > + > +static ssize_t sdw_slave_reg_read(struct file *file, char __user *user_buf, > + size_t count, loff_t *ppos) > +{ > + struct sdw_slave *slave = file->private_data; > + unsigned int reg; > + char *buf; > + ssize_t ret; > + int i, j; > + > + buf = kzalloc(RD_BUF, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + ret = scnprintf(buf, RD_BUF, "Register Value\n"); > + ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP0\n"); > + > + for (i = 0; i < 6; i++) > + ret += sdw_sprintf(slave, buf, ret, i); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); > + ret += sdw_sprintf(slave, buf, ret, SDW_DP0_CHANNELEN); > + for (i = SDW_DP0_SAMPLECTRL1; i <= SDW_DP0_LANECTRL; i++) > + ret += sdw_sprintf(slave, buf, ret, i); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); > + ret += sdw_sprintf(slave, buf, ret, > + SDW_DP0_CHANNELEN + SDW_BANK1_OFFSET); > + for (i = SDW_DP0_SAMPLECTRL1 + SDW_BANK1_OFFSET; > + i <= SDW_DP0_LANECTRL + SDW_BANK1_OFFSET; i++) > + ret += sdw_sprintf(slave, buf, ret, i); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "\nSCP\n"); > + for (i = SDW_SCP_INT1; i <= SDW_SCP_BANKDELAY; i++) > + ret += sdw_sprintf(slave, buf, ret, i); > + for (i = SDW_SCP_DEVID_0; i <= SDW_SCP_DEVID_5; i++) > + ret += sdw_sprintf(slave, buf, ret, i); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); > + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_FRAMECTRL_B0); > + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_NEXTFRAME_B0); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); > + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_FRAMECTRL_B1); > + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_NEXTFRAME_B1); > + > + for (i = 1; i < 14; i++) { > + ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP%d\n", i); > + reg = SDW_DPN_INT(i); > + for (j = 0; j < 6; j++) > + ret += sdw_sprintf(slave, buf, ret, reg + j); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); > + reg = SDW_DPN_CHANNELEN_B0(i); > + for (j = 0; j < 9; j++) > + ret += sdw_sprintf(slave, buf, ret, reg + j); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); > + reg = SDW_DPN_CHANNELEN_B1(i); > + for (j = 0; j < 9; j++) > + ret += sdw_sprintf(slave, buf, ret, reg + j); > + } > + > + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret); > + kfree(buf); > + > + return ret; > +} > + > +static const struct file_operations sdw_slave_reg_fops = { > + .open = simple_open, > + .read = sdw_slave_reg_read, > + .llseek = default_llseek, > +}; > + > +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave) > +{ > + struct sdw_bus_debugfs *master; > + struct sdw_slave_debugfs *d; > + char name[32]; > + > + master = slave->bus->debugfs; > + if (!master) > + return NULL; > + > + d = kzalloc(sizeof(*d), GFP_KERNEL); > + if (!d) > + return NULL; > + > + /* create the debugfs slave-name */ > + snprintf(name, sizeof(name), "%s", dev_name(&slave->dev)); > + d->fs = debugfs_create_dir(name, master->fs); > + if (IS_ERR_OR_NULL(d->fs)) { > + dev_err(&slave->dev, "slave debugfs root creation failed\n"); > + goto err; > + } You never care about the return value of a debugfs call. I have a 100+ patch series stripping all of this out of the kernel, please don't force me to add another one to it :) Just call debugfs and move on, you can always put the return value of one call into another one just fine, and your function logic should never change if debugfs returns an error or not, you do not care. > + > + d->slave = slave; > + > + debugfs_create_file("registers", 0400, d->fs, > + slave, &sdw_slave_reg_fops); > + > + return d; > + > +err: > + kfree(d); > + return NULL; > +} > + > +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d) > +{ > + debugfs_remove_recursive(d->fs); > + kfree(d); > +} > + > +void sdw_debugfs_init(void) > +{ > + sdw_debugfs_root = debugfs_create_dir("soundwire", NULL); > + if (IS_ERR_OR_NULL(sdw_debugfs_root)) { > + pr_warn("SoundWire: Failed to create debugfs directory\n"); > + sdw_debugfs_root = NULL; > + return; Same here, just call the function and return. thanks, greg k-h
>> @@ -136,6 +139,8 @@ static int sdw_delete_slave(struct device *dev, void *data) >> void sdw_delete_bus_master(struct sdw_bus *bus) >> { >> sdw_sysfs_bus_exit(bus); >> + if (bus->debugfs) >> + sdw_bus_debugfs_exit(bus->debugfs); > > No need to check, just call it. That was on my todo list, will remove. >> +struct sdw_bus_debugfs { >> + struct sdw_bus *bus; > > Why do you need to save this pointer? > >> + struct dentry *fs; > > This really is all you need to have around, right? will check. >> +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) >> +{ >> + if (d) >> + return d->fs; >> + return NULL; >> +} >> +EXPORT_SYMBOL(sdw_bus_debugfs_get_root); > > _GPL()? Oops, that's a big miss. will fix, thanks for spotting this. > > But why is this exported at all? No one calls this function. I will have to check. > >> +struct sdw_slave_debugfs { >> + struct sdw_slave *slave; > > Same question as above, why do you need this pointer? will check. > > And meta-comment, if you _EVER_ save off a pointer to a reference > counted object (like this and the above one), you HAVE to grab a > reference to it, otherwise it can go away at any point in time as that > is the point of reference counted objects. > > So even if you do need/want this, you have to properly handle the > reference count by incrementing/decrementing it as needed. good comment, thank you for the guidance. >> +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave) >> +{ >> + struct sdw_bus_debugfs *master; >> + struct sdw_slave_debugfs *d; >> + char name[32]; >> + >> + master = slave->bus->debugfs; >> + if (!master) >> + return NULL; >> + >> + d = kzalloc(sizeof(*d), GFP_KERNEL); >> + if (!d) >> + return NULL; >> + >> + /* create the debugfs slave-name */ >> + snprintf(name, sizeof(name), "%s", dev_name(&slave->dev)); >> + d->fs = debugfs_create_dir(name, master->fs); >> + if (IS_ERR_OR_NULL(d->fs)) { >> + dev_err(&slave->dev, "slave debugfs root creation failed\n"); >> + goto err; >> + } > > You never care about the return value of a debugfs call. I have a 100+ > patch series stripping all of this out of the kernel, please don't force > me to add another one to it :) > > Just call debugfs and move on, you can always put the return value of > one call into another one just fine, and your function logic should > never change if debugfs returns an error or not, you do not care. Yes, it's agreed that we should not depend on debugfs or fail here. will fix, no worries. > >> +void sdw_debugfs_init(void) >> +{ >> + sdw_debugfs_root = debugfs_create_dir("soundwire", NULL); >> + if (IS_ERR_OR_NULL(sdw_debugfs_root)) { >> + pr_warn("SoundWire: Failed to create debugfs directory\n"); >> + sdw_debugfs_root = NULL; >> + return; > > Same here, just call the function and return. yep, will do.
On 06-05-19, 09:48, Pierre-Louis Bossart wrote: > > > +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) > > > +{ > > > + if (d) > > > + return d->fs; > > > + return NULL; > > > +} > > > +EXPORT_SYMBOL(sdw_bus_debugfs_get_root); > > > > _GPL()? > > Oops, that's a big miss. will fix, thanks for spotting this. Not really. The Soundwire code is dual licensed. Many of the soundwire symbols are indeed exported as EXPORT_SYMBOL. But I agree this one is 'linux' specific so can be made _GPL. Pierre, does Intel still care about this being dual licensed or not? > > > > > But why is this exported at all? No one calls this function. > > I will have to check. It is used by codec driver which are not upstream yet. So my suggestion would be NOT to export this and only do so when we have users for it That would be true for other APIs exported out as well. > > > > > +struct sdw_slave_debugfs { > > > + struct sdw_slave *slave; > > > > Same question as above, why do you need this pointer? > > will check. The deubugfs code does hold a ref to slave object to read the data and dump, this particular instance might be able to get rid of (should be doable) > > And meta-comment, if you _EVER_ save off a pointer to a reference > > counted object (like this and the above one), you HAVE to grab a > > reference to it, otherwise it can go away at any point in time as that > > is the point of reference counted objects. > > > > So even if you do need/want this, you have to properly handle the > > reference count by incrementing/decrementing it as needed. Yes, but then device exit routine is supposed to do debugfs cleanup as well, so that would ensure these references are dropped at that point of time. Greg should that not take care of it or we *should* always do refcounting. Thanks
On 5/6/19 11:38 AM, Vinod Koul wrote: > On 06-05-19, 09:48, Pierre-Louis Bossart wrote: > >>>> +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) >>>> +{ >>>> + if (d) >>>> + return d->fs; >>>> + return NULL; >>>> +} >>>> +EXPORT_SYMBOL(sdw_bus_debugfs_get_root); >>> >>> _GPL()? >> >> Oops, that's a big miss. will fix, thanks for spotting this. > > Not really. The Soundwire code is dual licensed. Many of the soundwire > symbols are indeed exported as EXPORT_SYMBOL. But I agree this one is > 'linux' specific so can be made _GPL. > > Pierre, does Intel still care about this being dual licensed or not? Debugfs was never in scope for the dual-licensed parts, we've already agreed for SOF to move to _GPL. > >> >>> >>> But why is this exported at all? No one calls this function. >> >> I will have to check. > > It is used by codec driver which are not upstream yet. So my suggestion > would be NOT to export this and only do so when we have users for it > That would be true for other APIs exported out as well. It'll just make the first codec driver patchset more complicated but fine.
On Mon, May 06, 2019 at 10:08:10PM +0530, Vinod Koul wrote: > Yes, but then device exit routine is supposed to do debugfs cleanup as > well, so that would ensure these references are dropped at that point of > time. Greg should that not take care of it or we *should* always do > refcounting. Always do refcounting. How else can you "guarantee" that it is safe?
diff --git a/drivers/soundwire/Makefile b/drivers/soundwire/Makefile index a72a29731a28..f2c425fa15bd 100644 --- a/drivers/soundwire/Makefile +++ b/drivers/soundwire/Makefile @@ -4,7 +4,8 @@ #Bus Objs soundwire-bus-objs := bus_type.o bus.o slave.o mipi_disco.o stream.o \ - sysfs.o sysfs_slave_dp0.o sysfs_slave_dpn.o + sysfs.o sysfs_slave_dp0.o sysfs_slave_dpn.o \ + debugfs.o obj-$(CONFIG_SOUNDWIRE_BUS) += soundwire-bus.o #Cadence Objs diff --git a/drivers/soundwire/bus.c b/drivers/soundwire/bus.c index dd9181693554..b79eba321b71 100644 --- a/drivers/soundwire/bus.c +++ b/drivers/soundwire/bus.c @@ -53,6 +53,8 @@ int sdw_add_bus_master(struct sdw_bus *bus) if (ret < 0) dev_warn(bus->dev, "Bus sysfs init failed:%d\n", ret); + bus->debugfs = sdw_bus_debugfs_init(bus); + /* * Device numbers in SoundWire are 0 through 15. Enumeration device * number (0), Broadcast device number (15), Group numbers (12 and @@ -114,6 +116,7 @@ static int sdw_delete_slave(struct device *dev, void *data) struct sdw_bus *bus = slave->bus; sdw_sysfs_slave_exit(slave); + sdw_slave_debugfs_exit(slave->debugfs); mutex_lock(&bus->bus_lock); @@ -136,6 +139,8 @@ static int sdw_delete_slave(struct device *dev, void *data) void sdw_delete_bus_master(struct sdw_bus *bus) { sdw_sysfs_bus_exit(bus); + if (bus->debugfs) + sdw_bus_debugfs_exit(bus->debugfs); device_for_each_child(bus->dev, NULL, sdw_delete_slave); } diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 0707e68a8d21..f0b1f4f9d7b2 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -20,6 +20,34 @@ void sdw_extract_slave_id(struct sdw_bus *bus, extern const struct attribute_group *sdw_slave_dev_attr_groups[]; +#ifdef CONFIG_DEBUG_FS +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus); +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d); +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d); +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave); +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d); +void sdw_debugfs_init(void); +void sdw_debugfs_exit(void); +#else +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus) +{ return NULL; } + +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d) {} + +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) +{ return NULL; } + +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave) +{ return NULL; } + +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d) {} + +void sdw_debugfs_init(void) {} + +void sdw_debugfs_exit(void) {} + +#endif + enum { SDW_MSG_FLAG_READ = 0, SDW_MSG_FLAG_WRITE, diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index f68fe45c1037..f28c1a2446af 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -6,6 +6,7 @@ #include <linux/pm_domain.h> #include <linux/soundwire/sdw.h> #include <linux/soundwire/sdw_type.h> +#include "bus.h" /** * sdw_get_device_id - find the matching SoundWire device id @@ -182,11 +183,13 @@ EXPORT_SYMBOL_GPL(sdw_unregister_driver); static int __init sdw_bus_init(void) { + sdw_debugfs_init(); return bus_register(&sdw_bus_type); } static void __exit sdw_bus_exit(void) { + sdw_debugfs_exit(); bus_unregister(&sdw_bus_type); } diff --git a/drivers/soundwire/debugfs.c b/drivers/soundwire/debugfs.c new file mode 100644 index 000000000000..8a8b4df95c46 --- /dev/null +++ b/drivers/soundwire/debugfs.c @@ -0,0 +1,214 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) +// Copyright(c) 2017-19 Intel Corporation. + +#include <linux/device.h> +#include <linux/debugfs.h> +#include <linux/mod_devicetable.h> +#include <linux/slab.h> +#include <linux/soundwire/sdw.h> +#include <linux/soundwire/sdw_registers.h> +#include "bus.h" + +#ifdef CONFIG_DEBUG_FS +struct dentry *sdw_debugfs_root; +#endif + +struct sdw_bus_debugfs { + struct sdw_bus *bus; + + struct dentry *fs; +}; + +struct sdw_bus_debugfs *sdw_bus_debugfs_init(struct sdw_bus *bus) +{ + struct sdw_bus_debugfs *d; + char name[16]; + + if (!sdw_debugfs_root) + return NULL; + + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) + return NULL; + + /* create the debugfs master-N */ + snprintf(name, sizeof(name), "master-%d", bus->link_id); + d->fs = debugfs_create_dir(name, sdw_debugfs_root); + if (IS_ERR_OR_NULL(d->fs)) { + dev_err(bus->dev, "debugfs root creation failed\n"); + goto err; + } + + d->bus = bus; + + return d; + +err: + kfree(d); + return NULL; +} + +void sdw_bus_debugfs_exit(struct sdw_bus_debugfs *d) +{ + debugfs_remove_recursive(d->fs); + kfree(d); +} + +struct dentry *sdw_bus_debugfs_get_root(struct sdw_bus_debugfs *d) +{ + if (d) + return d->fs; + return NULL; +} +EXPORT_SYMBOL(sdw_bus_debugfs_get_root); + +struct sdw_slave_debugfs { + struct sdw_slave *slave; + + struct dentry *fs; +}; + +#define RD_BUF (3 * PAGE_SIZE) + +static ssize_t sdw_sprintf(struct sdw_slave *slave, + char *buf, size_t pos, unsigned int reg) +{ + int value; + + value = sdw_read(slave, reg); + + if (value < 0) + return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg); + else + return scnprintf(buf + pos, RD_BUF - pos, + "%3x\t%2x\n", reg, value); +} + +static ssize_t sdw_slave_reg_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct sdw_slave *slave = file->private_data; + unsigned int reg; + char *buf; + ssize_t ret; + int i, j; + + buf = kzalloc(RD_BUF, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = scnprintf(buf, RD_BUF, "Register Value\n"); + ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP0\n"); + + for (i = 0; i < 6; i++) + ret += sdw_sprintf(slave, buf, ret, i); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); + ret += sdw_sprintf(slave, buf, ret, SDW_DP0_CHANNELEN); + for (i = SDW_DP0_SAMPLECTRL1; i <= SDW_DP0_LANECTRL; i++) + ret += sdw_sprintf(slave, buf, ret, i); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); + ret += sdw_sprintf(slave, buf, ret, + SDW_DP0_CHANNELEN + SDW_BANK1_OFFSET); + for (i = SDW_DP0_SAMPLECTRL1 + SDW_BANK1_OFFSET; + i <= SDW_DP0_LANECTRL + SDW_BANK1_OFFSET; i++) + ret += sdw_sprintf(slave, buf, ret, i); + + ret += scnprintf(buf + ret, RD_BUF - ret, "\nSCP\n"); + for (i = SDW_SCP_INT1; i <= SDW_SCP_BANKDELAY; i++) + ret += sdw_sprintf(slave, buf, ret, i); + for (i = SDW_SCP_DEVID_0; i <= SDW_SCP_DEVID_5; i++) + ret += sdw_sprintf(slave, buf, ret, i); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_FRAMECTRL_B0); + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_NEXTFRAME_B0); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_FRAMECTRL_B1); + ret += sdw_sprintf(slave, buf, ret, SDW_SCP_NEXTFRAME_B1); + + for (i = 1; i < 14; i++) { + ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP%d\n", i); + reg = SDW_DPN_INT(i); + for (j = 0; j < 6; j++) + ret += sdw_sprintf(slave, buf, ret, reg + j); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n"); + reg = SDW_DPN_CHANNELEN_B0(i); + for (j = 0; j < 9; j++) + ret += sdw_sprintf(slave, buf, ret, reg + j); + + ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n"); + reg = SDW_DPN_CHANNELEN_B1(i); + for (j = 0; j < 9; j++) + ret += sdw_sprintf(slave, buf, ret, reg + j); + } + + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret); + kfree(buf); + + return ret; +} + +static const struct file_operations sdw_slave_reg_fops = { + .open = simple_open, + .read = sdw_slave_reg_read, + .llseek = default_llseek, +}; + +struct sdw_slave_debugfs *sdw_slave_debugfs_init(struct sdw_slave *slave) +{ + struct sdw_bus_debugfs *master; + struct sdw_slave_debugfs *d; + char name[32]; + + master = slave->bus->debugfs; + if (!master) + return NULL; + + d = kzalloc(sizeof(*d), GFP_KERNEL); + if (!d) + return NULL; + + /* create the debugfs slave-name */ + snprintf(name, sizeof(name), "%s", dev_name(&slave->dev)); + d->fs = debugfs_create_dir(name, master->fs); + if (IS_ERR_OR_NULL(d->fs)) { + dev_err(&slave->dev, "slave debugfs root creation failed\n"); + goto err; + } + + d->slave = slave; + + debugfs_create_file("registers", 0400, d->fs, + slave, &sdw_slave_reg_fops); + + return d; + +err: + kfree(d); + return NULL; +} + +void sdw_slave_debugfs_exit(struct sdw_slave_debugfs *d) +{ + debugfs_remove_recursive(d->fs); + kfree(d); +} + +void sdw_debugfs_init(void) +{ + sdw_debugfs_root = debugfs_create_dir("soundwire", NULL); + if (IS_ERR_OR_NULL(sdw_debugfs_root)) { + pr_warn("SoundWire: Failed to create debugfs directory\n"); + sdw_debugfs_root = NULL; + return; + } +} + +void sdw_debugfs_exit(void) +{ + debugfs_remove_recursive(sdw_debugfs_root); +} diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c index bad73a267fdd..e41332a7f340 100644 --- a/drivers/soundwire/slave.c +++ b/drivers/soundwire/slave.c @@ -57,6 +57,7 @@ static int sdw_slave_add(struct sdw_bus *bus, mutex_unlock(&bus->bus_lock); put_device(&slave->dev); } + slave->debugfs = sdw_slave_debugfs_init(slave); return ret; } diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index fae3a3ad6e68..3684ca106408 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -547,6 +547,8 @@ struct sdw_slave_ops { enum sdw_port_prep_ops pre_ops); }; +struct sdw_slave_debugfs; + /** * struct sdw_slave - SoundWire Slave * @id: MIPI device ID @@ -556,6 +558,7 @@ struct sdw_slave_ops { * @ops: Slave callback ops * @prop: Slave properties * @sysfs: Sysfs interface + * @debugfs: Slave debugfs * @node: node for bus list * @port_ready: Port ready completion flag for each Slave port * @dev_num: Device Number assigned by Bus @@ -568,6 +571,7 @@ struct sdw_slave { const struct sdw_slave_ops *ops; struct sdw_slave_prop prop; struct sdw_slave_sysfs *sysfs; + struct sdw_slave_debugfs *debugfs; struct list_head node; struct completion *port_ready; u16 dev_num; @@ -728,6 +732,8 @@ struct sdw_master_ops { }; +struct sdw_bus_debugfs; + /** * struct sdw_bus - SoundWire bus * @dev: Master linux device @@ -742,8 +748,10 @@ struct sdw_master_ops { * @params: Current bus parameters * @prop: Master properties * @m_rt_list: List of Master instance of all stream(s) running on Bus. This + * @rt_list: List of Master instance of all stream(s) running on Bus. This * is used to compute and program bus bandwidth, clock, frame shape, * transport and port parameters + * @debugfs: Bus debugfs * @sysfs: Bus sysfs * @defer_msg: Defer message * @clk_stop_timeout: Clock stop timeout computed @@ -765,6 +773,7 @@ struct sdw_bus { struct sdw_master_prop prop; struct list_head m_rt_list; struct sdw_master_sysfs *sysfs; + struct sdw_bus_debugfs *debugfs; struct sdw_defer defer_msg; unsigned int clk_stop_timeout; u32 bank_switch_timeout;
Add base debugfs mechanism for SoundWire bus by creating soundwire root and master-N and slave-x hierarchy. Also add SDW Slave SCP, DP0 and DP-N register debug file. Registers not implemented will print as "XX" Credits: this patch is based on an earlier internal contribution by Vinod Koul, Sanyog Kale, Shreyas Nc and Hardik Shah. The main change is the use of scnprintf to avoid known issues with snprintf. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> --- drivers/soundwire/Makefile | 3 +- drivers/soundwire/bus.c | 5 + drivers/soundwire/bus.h | 28 +++++ drivers/soundwire/bus_type.c | 3 + drivers/soundwire/debugfs.c | 214 ++++++++++++++++++++++++++++++++++ drivers/soundwire/slave.c | 1 + include/linux/soundwire/sdw.h | 9 ++ 7 files changed, 262 insertions(+), 1 deletion(-) create mode 100644 drivers/soundwire/debugfs.c