Hi Pierre, A couple of nitpicks: On Thu, Jul 25, 2019 at 06:39:53PM -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@xxxxxxxxxxxxxxx> > --- > drivers/soundwire/Makefile | 4 +- > drivers/soundwire/bus.c | 6 ++ > drivers/soundwire/bus.h | 24 ++++++ > drivers/soundwire/bus_type.c | 3 + > drivers/soundwire/debugfs.c | 156 ++++++++++++++++++++++++++++++++++ > drivers/soundwire/slave.c | 1 + > include/linux/soundwire/sdw.h | 4 + > 7 files changed, 197 insertions(+), 1 deletion(-) > create mode 100644 drivers/soundwire/debugfs.c [snip] > diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h > index 3048ca153f22..06ac4adb0074 100644 > --- a/drivers/soundwire/bus.h > +++ b/drivers/soundwire/bus.h > @@ -18,6 +18,30 @@ static inline int sdw_acpi_find_slaves(struct sdw_bus *bus) > void sdw_extract_slave_id(struct sdw_bus *bus, > u64 addr, struct sdw_slave_id *id); > > +#ifdef CONFIG_DEBUG_FS > +struct dentry *sdw_bus_debugfs_init(struct sdw_bus *bus); > +void sdw_bus_debugfs_exit(struct dentry *d); > +struct dentry *sdw_slave_debugfs_init(struct sdw_slave *slave); > +void sdw_slave_debugfs_exit(struct dentry *d); > +void sdw_debugfs_init(void); > +void sdw_debugfs_exit(void); > +#else > +struct dentry *sdw_bus_debugfs_init(struct sdw_bus *bus) > +{ return NULL; } static? > + > +void sdw_bus_debugfs_exit(struct dentry *d) {} > + > +struct dentry *sdw_slave_debugfs_init(struct sdw_slave *slave) > +{ return NULL; } > + > +void sdw_slave_debugfs_exit(struct dentry *d) {} > + > +void sdw_debugfs_init(void) {} > + > +void sdw_debugfs_exit(void) {} Same for all the above. You could also declare them inline, but I really hope the compiler will be smart enough to do that itself. > + > +#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 2655602f0cfb..4a465f55039f 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 > @@ -177,11 +178,13 @@ 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..8d86e100516e > --- /dev/null > +++ b/drivers/soundwire/debugfs.c > @@ -0,0 +1,156 @@ > +// 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 dentry *sdw_bus_debugfs_init(struct sdw_bus *bus) > +{ > + struct dentry *d; I would remove the above > + char name[16]; > + > + if (!sdw_debugfs_root) > + return NULL; > + > + /* create the debugfs master-N */ > + snprintf(name, sizeof(name), "master-%d", bus->link_id); > + d = debugfs_create_dir(name, sdw_debugfs_root); > + > + return d; And just do + return debugfs_create_dir(name, sdw_debugfs_root); > +} > + > +void sdw_bus_debugfs_exit(struct dentry *d) > +{ > + debugfs_remove_recursive(d); > +} > + > +#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); I personally would join the two lines above, but that's just a personal preference. > + > + if (value < 0) > + return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg); > + else I think it's advised to not use an else in such cases. Thanks Guennadi > + 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 dentry *sdw_slave_debugfs_init(struct sdw_slave *slave) > +{ > + struct dentry *master; > + struct dentry *d; > + char name[32]; > + > + master = slave->bus->debugfs; > + > + /* create the debugfs slave-name */ > + snprintf(name, sizeof(name), "%s", dev_name(&slave->dev)); > + d = debugfs_create_dir(name, master); > + > + debugfs_create_file("registers", 0400, d, slave, &sdw_slave_reg_fops); > + > + return d; > +} > + > +void sdw_slave_debugfs_exit(struct dentry *d) > +{ > + debugfs_remove_recursive(d); > +} > + > +void sdw_debugfs_init(void) > +{ > + sdw_debugfs_root = debugfs_create_dir("soundwire", NULL); > +} > + > +void sdw_debugfs_exit(void) > +{ > + debugfs_remove_recursive(sdw_debugfs_root); > +} > diff --git a/drivers/soundwire/slave.c b/drivers/soundwire/slave.c > index f39a5815e25d..34d8bb995f45 100644 > --- a/drivers/soundwire/slave.c > +++ b/drivers/soundwire/slave.c > @@ -56,6 +56,7 @@ 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 3b231472464a..a49028e9d666 100644 > --- a/include/linux/soundwire/sdw.h > +++ b/include/linux/soundwire/sdw.h > @@ -544,6 +544,7 @@ struct sdw_slave_ops { > * @bus: Bus handle > * @ops: Slave callback ops > * @prop: Slave properties > + * @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 > @@ -555,6 +556,7 @@ struct sdw_slave { > struct sdw_bus *bus; > const struct sdw_slave_ops *ops; > struct sdw_slave_prop prop; > + struct dentry *debugfs; > struct list_head node; > struct completion *port_ready; > u16 dev_num; > @@ -731,6 +733,7 @@ struct sdw_master_ops { > * @m_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 > * @defer_msg: Defer message > * @clk_stop_timeout: Clock stop timeout computed > * @bank_switch_timeout: Bank switch timeout computed > @@ -750,6 +753,7 @@ struct sdw_bus { > struct sdw_bus_params params; > struct sdw_master_prop prop; > struct list_head m_rt_list; > + struct dentry *debugfs; > struct sdw_defer defer_msg; > unsigned int clk_stop_timeout; > u32 bank_switch_timeout; > -- > 2.20.1 > > _______________________________________________ > Alsa-devel mailing list > Alsa-devel@xxxxxxxxxxxxxxxx > https://mailman.alsa-project.org/mailman/listinfo/alsa-devel _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel