On Thu, Jul 25, 2019 at 06:39:54PM -0500, Pierre-Louis Bossart wrote: > Add debugfs file to dump the Cadence master registers > > 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/cadence_master.c | 98 ++++++++++++++++++++++++++++++ > drivers/soundwire/cadence_master.h | 2 + > 2 files changed, 100 insertions(+) > > diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c > index ff4badc9b3de..91e8bacb83e3 100644 > --- a/drivers/soundwire/cadence_master.c > +++ b/drivers/soundwire/cadence_master.c > @@ -8,6 +8,7 @@ > > #include <linux/delay.h> > #include <linux/device.h> > +#include <linux/debugfs.h> > #include <linux/interrupt.h> > #include <linux/io.h> > #include <linux/module.h> > @@ -223,6 +224,103 @@ static int cdns_clear_bit(struct sdw_cdns *cdns, int offset, u32 value) > return -EAGAIN; > } > > +/* > + * debugfs > + */ > + > +#define RD_BUF (2 * PAGE_SIZE) > + > +static ssize_t cdns_sprintf(struct sdw_cdns *cdns, > + char *buf, size_t pos, unsigned int reg) > +{ > + return scnprintf(buf + pos, RD_BUF - pos, > + "%4x\t%4x\n", reg, cdns_readl(cdns, reg)); > +} > + > +static ssize_t cdns_reg_read(struct file *file, char __user *user_buf, > + size_t count, loff_t *ppos) > +{ > + struct sdw_cdns *cdns = file->private_data; > + 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, "\nMCP Registers\n"); > + for (i = 0; i < 8; i++) /* 8 MCP registers */ > + ret += cdns_sprintf(cdns, buf, ret, i * 4); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nStatus & Intr Registers\n"); > + for (i = 0; i < 13; i++) /* 13 Status & Intr registers */ > + ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_STAT + i * 4); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nSSP & Clk ctrl Registers\n"); > + ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_SSP_CTRL0); > + ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_SSP_CTRL1); > + ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_CLK_CTRL0); > + ret += cdns_sprintf(cdns, buf, ret, CDNS_MCP_CLK_CTRL1); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nDPn B0 Registers\n"); > + for (i = 0; i < 7; i++) { > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nDP-%d\n", i); > + for (j = 0; j < 6; j++) > + ret += cdns_sprintf(cdns, buf, ret, > + CDNS_DPN_B0_CONFIG(i) + j * 4); > + } > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nDPn B1 Registers\n"); > + for (i = 0; i < 7; i++) { > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nDP-%d\n", i); > + > + for (j = 0; j < 6; j++) > + ret += cdns_sprintf(cdns, buf, ret, > + CDNS_DPN_B1_CONFIG(i) + j * 4); > + } > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nDPn Control Registers\n"); > + for (i = 0; i < 7; i++) > + ret += cdns_sprintf(cdns, buf, ret, > + CDNS_PORTCTRL + i * CDNS_PORT_OFFSET); > + > + ret += scnprintf(buf + ret, RD_BUF - ret, > + "\nPDIn Config Registers\n"); > + for (i = 0; i < 7; i++) > + ret += cdns_sprintf(cdns, buf, ret, CDNS_PDI_CONFIG(i)); > + > + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret); > + kfree(buf); > + > + return ret; > +} > + > +static const struct file_operations cdns_reg_fops = { > + .open = simple_open, > + .read = cdns_reg_read, > + .llseek = default_llseek, > +}; DEFINE_SHOW_ATTRIBUTE()? thanks, greg k-h _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx https://mailman.alsa-project.org/mailman/listinfo/alsa-devel