From: Angelo Dureghello <adureghello@xxxxxxxxxxxx> The ad3552r can be feeded from the HDL controller by an internally generated 16bit ramp, useful for debug pourposes. Add debugfs a file to enable or disable it. Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx> --- drivers/iio/dac/ad3552r-hs.c | 122 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 116 insertions(+), 6 deletions(-) diff --git a/drivers/iio/dac/ad3552r-hs.c b/drivers/iio/dac/ad3552r-hs.c index 37397e188f225a8099745ec03f7c604da76960b1..d4f50b33565f99b90859e30571dc59038d01361c 100644 --- a/drivers/iio/dac/ad3552r-hs.c +++ b/drivers/iio/dac/ad3552r-hs.c @@ -7,6 +7,7 @@ */ #include <linux/bitfield.h> +#include <linux/debugfs.h> #include <linux/delay.h> #include <linux/gpio/consumer.h> #include <linux/iio/backend.h> @@ -54,8 +55,12 @@ struct ad3552r_hs_state { struct ad3552r_hs_platform_data *data; /* INTERFACE_CONFIG_D register cache, in DDR we cannot read values. */ u32 config_d; + struct mutex lock; }; +static const char dbgfs_src_iio_buffer[] = "iio-buffer"; +static const char dbgfs_src_backend_ramp_gen[] = "backend-ramp-generator"; + static int ad3552r_hs_reg_read(struct ad3552r_hs_state *st, u32 reg, u32 *val, size_t xfer_size) { @@ -65,6 +70,18 @@ static int ad3552r_hs_reg_read(struct ad3552r_hs_state *st, u32 reg, u32 *val, return st->data->bus_reg_read(st->back, reg, val, xfer_size); } +static int ad3552r_hs_set_data_source(struct ad3552r_hs_state *st, + enum iio_backend_data_source type) +{ + int ret; + + ret = iio_backend_data_source_set(st->back, 0, type); + if (ret) + return ret; + + return iio_backend_data_source_set(st->back, 1, type); +} + static int ad3552r_hs_update_reg_bits(struct ad3552r_hs_state *st, u32 reg, u32 mask, u32 val, size_t xfer_size) { @@ -483,6 +500,76 @@ static int ad3552r_hs_reg_access(struct iio_dev *indio_dev, unsigned int reg, return st->data->bus_reg_write(st->back, reg, writeval, 1); } +static ssize_t ad3552r_hs_show_data_source(struct file *f, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct ad3552r_hs_state *st = file_inode(f)->i_private; + enum iio_backend_data_source type; + int ret; + + guard(mutex)(&st->lock); + + ret = iio_backend_data_source_get(st->back, 0, &type); + if (ret) + return ret; + + switch (type) { + case IIO_BACKEND_INTERNAL_RAMP_16BIT: + return simple_read_from_buffer(userbuf, count, ppos, + dbgfs_src_backend_ramp_gen, + strlen(dbgfs_src_backend_ramp_gen)); + case IIO_BACKEND_EXTERNAL: + return simple_read_from_buffer(userbuf, count, ppos, + dbgfs_src_iio_buffer, strlen(dbgfs_src_iio_buffer)); + default: + return -EINVAL; + } +} + +static ssize_t ad3552r_hs_write_data_source(struct file *f, + const char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct ad3552r_hs_state *st = file_inode(f)->i_private; + char buf[64]; + int ret, len; + + guard(mutex)(&st->lock); + + ret = simple_write_to_buffer(buf, sizeof(buf) - 1, ppos, userbuf, + count); + if (ret < 0) + return ret; + + len = strlen(dbgfs_src_iio_buffer); + if (count == len && !strncmp(buf, dbgfs_src_iio_buffer, len)) { + ret = ad3552r_hs_set_data_source(st, IIO_BACKEND_EXTERNAL); + if (ret) + return ret; + goto exit_ok; + } + + len = strlen(dbgfs_src_backend_ramp_gen); + if (count == len && !strncmp(buf, dbgfs_src_backend_ramp_gen, len)) { + ret = ad3552r_hs_set_data_source(st, + IIO_BACKEND_INTERNAL_RAMP_16BIT); + if (ret) + return ret; + goto exit_ok; + } + + return -EINVAL; + +exit_ok: + return count; +} + +static const struct file_operations ad3552r_hs_data_source_fops = { + .owner = THIS_MODULE, + .write = ad3552r_hs_write_data_source, + .read = ad3552r_hs_show_data_source, +}; + static int ad3552r_hs_setup(struct ad3552r_hs_state *st) { u16 id; @@ -550,11 +637,7 @@ static int ad3552r_hs_setup(struct ad3552r_hs_state *st) if (ret) return ret; - ret = iio_backend_data_source_set(st->back, 0, IIO_BACKEND_EXTERNAL); - if (ret) - return ret; - - ret = iio_backend_data_source_set(st->back, 1, IIO_BACKEND_EXTERNAL); + ret = ad3552r_hs_set_data_source(st, IIO_BACKEND_EXTERNAL); if (ret) return ret; @@ -661,6 +744,24 @@ static const struct iio_info ad3552r_hs_info = { .debugfs_reg_access = &ad3552r_hs_reg_access, }; +static void ad3552r_hs_debugfs_init(struct iio_dev *indio_dev) +{ + struct ad3552r_hs_state *st = iio_priv(indio_dev); + struct dentry *d = iio_get_debugfs_dentry(indio_dev); + + if (!IS_ENABLED(CONFIG_DEBUG_FS)) + return; + + d = iio_get_debugfs_dentry(indio_dev); + if (!d) { + dev_warn(st->dev, "can't set debugfs in driver dir\n"); + return; + } + + debugfs_create_file("data_source", 0600, d, st, + &ad3552r_hs_data_source_fops); +} + static int ad3552r_hs_probe(struct platform_device *pdev) { struct ad3552r_hs_state *st; @@ -705,7 +806,16 @@ static int ad3552r_hs_probe(struct platform_device *pdev) if (ret) return ret; - return devm_iio_device_register(&pdev->dev, indio_dev); + ret = devm_iio_device_register(&pdev->dev, indio_dev); + if (ret) + return ret; + + mutex_init(&st->lock); + + ad3552r_hs_debugfs_init(indio_dev); + + return ret; + } static const struct of_device_id ad3552r_hs_of_id[] = { -- 2.49.0