Re: [PATCH v6 5/8] usb: typec: cros_ec_ucsi: Add trace events

Heikki Krogerus
2024-09-11T13:36:08Z

On Tue, Sep 10, 2024 at 10:15:24AM +0000, Łukasz Bartosik wrote:
> Add trace events to ChromeOS UCSI driver to enable debugging.
>
> Signed-off-by: Łukasz Bartosik <ukaszb@chromium.org>
> ---
> MAINTAINERS | 1 +
> drivers/usb/typec/ucsi/cros_ec_ucsi.c | 8 ++
> drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h | 92 +++++++++++++++++++++
> 3 files changed, 101 insertions(+)
> create mode 100644 drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8c030ea0b503..d084f32208f0 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -5306,6 +5306,7 @@ M: Łukasz Bartosik <ukaszb@chromium.org>
> L: chrome-platform@lists.linux.dev
> S: Maintained
> F: drivers/usb/typec/ucsi/cros_ec_ucsi.c
> +F: drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h
>
> CHRONTEL CH7322 CEC DRIVER
> M: Joe Tessler <jrt@google.com>
> diff --git a/drivers/usb/typec/ucsi/cros_ec_ucsi.c b/drivers/usb/typec/ucsi/cros_ec_ucsi.c
> index 422b3b14028c..70185616ec86 100644
> --- a/drivers/usb/typec/ucsi/cros_ec_ucsi.c
> +++ b/drivers/usb/typec/ucsi/cros_ec_ucsi.c
> @@ -16,7 +16,9 @@
> #include <linux/slab.h>
> #include <linux/wait.h>
>
> +#define CREATE_TRACE_POINTS
> #include "ucsi.h"
> +#include "cros_ec_ucsi_trace.h"
>
> /*
> * Maximum size in bytes of a UCSI message between AP and EC
> @@ -62,6 +64,8 @@ static int cros_ucsi_read(struct ucsi *ucsi, unsigned int offset, void *val,
> dev_warn(udata->dev, "Failed to send EC message UCSI_PPM_GET: error=%d", ret);
> return ret;
> }
> +
> + trace_cros_ec_opm_to_ppm_rd(offset, val, val_len);
> return 0;
> }
>
> @@ -96,6 +100,8 @@ static int cros_ucsi_async_control(struct ucsi *ucsi, u64 cmd)
> dev_warn(udata->dev, "Failed to send EC message UCSI_PPM_SET: error=%d", ret);
> return ret;
> }
> +
> + trace_cros_ec_opm_to_ppm_wr(req->offset, &cmd, sizeof(cmd));
> return 0;
> }
>
> @@ -138,6 +144,8 @@ static void cros_ucsi_work(struct work_struct *work)
> struct cros_ucsi_data *udata = container_of(work, struct cros_ucsi_data, work);
> u32 cci;
>
> + trace_cros_ec_ppm_to_opm(0);
> +
> if (cros_ucsi_read_cci(udata->ucsi, &cci))
> return;
>
> diff --git a/drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h b/drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h
> new file mode 100644
> index 000000000000..b765ef5c8236
> --- /dev/null
> +++ b/drivers/usb/typec/ucsi/cros_ec_ucsi_trace.h
> @@ -0,0 +1,92 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +
> +#undef TRACE_SYSTEM
> +#define TRACE_SYSTEM cros_ec_ucsi
> +
> +#if !defined(__CROS_EC_UCSI_TRACE_H) || defined(TRACE_HEADER_MULTI_READ)
> +#define __CROS_EC_UCSI_TRACE_H
> +
> +#include <linux/tracepoint.h>
> +
> +#define decode_cmd(cmd) \
> + __print_symbolic(cmd, \
> + { 0, "Unknown command" }, \
> + { UCSI_PPM_RESET, "PPM_RESET" }, \
> + { UCSI_CONNECTOR_RESET, "CONNECTOR_RESET," }, \
> + { UCSI_ACK_CC_CI, "ACK_CC_CI" }, \
> + { UCSI_SET_NOTIFICATION_ENABLE, "SET_NOTIFICATION_ENABLE" }, \
> + { UCSI_GET_CAPABILITY, "GET_CAPABILITY" }, \
> + { UCSI_GET_CONNECTOR_CAPABILITY, "GET_CONNECTOR_CAPABILITY" }, \
> + { UCSI_SET_UOM, "SET_UOM" }, \
> + { UCSI_SET_UOR, "SET_UOR" }, \
> + { UCSI_SET_PDM, "SET_PDM" }, \
> + { UCSI_SET_PDR, "SET_PDR" }, \
> + { UCSI_GET_ALTERNATE_MODES, "GET_ALTERNATE_MODES" }, \
> + { UCSI_GET_CAM_SUPPORTED, "GET_CAM_SUPPORTED" }, \
> + { UCSI_GET_CURRENT_CAM, "GET_CURRENT_CAM" }, \
> + { UCSI_SET_NEW_CAM, "SET_NEW_CAM" }, \
> + { UCSI_GET_PDOS, "GET_PDOS" }, \
> + { UCSI_GET_CABLE_PROPERTY, "GET_CABLE_PROPERTY" }, \
> + { UCSI_GET_CONNECTOR_STATUS, "GET_CONNECTOR_STATUS" }, \
> + { UCSI_GET_ERROR_STATUS, "GET_ERROR_STATUS" })

Couldn't you just export ucsi_cmd_str() ?

> +#define decode_offset(offset) \
> + __print_symbolic(offset, \
> + { UCSI_VERSION, "VER" }, \
> + { UCSI_CCI, "CCI" }, \
> + { UCSI_CONTROL, "CTRL" }, \
> + { UCSI_MESSAGE_IN, "MSG_IN" }, \
> + { UCSI_MESSAGE_OUT, "MSG_OUT" }, \
> + { UCSIv2_MESSAGE_OUT, "MSG_OUTv2" })
> +
> +DECLARE_EVENT_CLASS(cros_ec_opm_to_ppm,
> + TP_PROTO(u16 offset, const void *value, size_t length),
> + TP_ARGS(offset, value, length),
> + TP_STRUCT__entry(
> + __field(u8, cmd)
> + __field(u16, offset)
> + __field(size_t, length)
> + __dynamic_array(char, msg, length)
> + ),
> + TP_fast_assign(
> + __entry->cmd = *((u64 *) value + 3);
> + __entry->offset = offset;
> + __entry->length = length;
> + memcpy(__get_dynamic_array(msg), value, length);
> + ),
> + TP_printk("(%s) %s: %s",
> + decode_offset(__entry->offset),
> + __entry->offset == UCSI_CONTROL ?
> + decode_cmd(__entry->cmd) : "",
> + __print_hex(__get_dynamic_array(msg), __entry->length))
> +);
> +
> +DEFINE_EVENT(cros_ec_opm_to_ppm, cros_ec_opm_to_ppm_rd,
> + TP_PROTO(u16 offset, const void *value, size_t length),
> + TP_ARGS(offset, value, length)
> +);
> +
> +DEFINE_EVENT(cros_ec_opm_to_ppm, cros_ec_opm_to_ppm_wr,
> + TP_PROTO(u16 offset, const void *value, size_t length),
> + TP_ARGS(offset, value, length)
> +);
> +
> +TRACE_EVENT(cros_ec_ppm_to_opm,
> + TP_PROTO(int x),
> + TP_ARGS(x),
> + TP_STRUCT__entry(__array(char, x, 0)),
> + TP_fast_assign((void)x),
> + TP_printk("notification%s", "")
> +);

This does not look cros_ec specific. Could you check if this could be
made part of the ucsi core tracepoints?

I can also look into this more carefully, and throw ideas if you like.
Let me know.

Br,

--
heikki