2021-02-14 11:24:13

by Kyle Tso

[permalink] [raw]
Subject: [PATCH v3] usb: typec: tcpm: Export partner Source Capabilities

Export a function for other drivers to get the partner Source
Capabilities.

Signed-off-by: Kyle Tso <[email protected]>
---
Changes since v1:
- add a put function to free the memory

Changes since v2:
- bring back the function tcpm_copy_pdos

drivers/usb/typec/tcpm/tcpm.c | 47 +++++++++++++++++++++++++++++++++++
include/linux/usb/tcpm.h | 2 ++
2 files changed, 49 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c
index be0b6469dd3d..1679c75e5a3d 100644
--- a/drivers/usb/typec/tcpm/tcpm.c
+++ b/drivers/usb/typec/tcpm/tcpm.c
@@ -5739,6 +5739,53 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
return 0;
}

+static int tcpm_copy_pdos(u32 *dest_pdo, const u32 *src_pdo, unsigned int nr_pdo)
+{
+ unsigned int i;
+
+ if (nr_pdo > PDO_MAX_OBJECTS)
+ nr_pdo = PDO_MAX_OBJECTS;
+
+ for (i = 0; i < nr_pdo; i++)
+ dest_pdo[i] = src_pdo[i];
+
+ return nr_pdo;
+}
+
+/*
+ * Don't call this function in interrupt context. Caller needs to free the
+ * memory by calling tcpm_put_partner_src_caps.
+ */
+int tcpm_get_partner_src_caps(struct tcpm_port *port, u32 **src_pdo)
+{
+ unsigned int nr_pdo;
+
+ mutex_lock(&port->lock);
+ if (port->nr_source_caps == 0) {
+ mutex_unlock(&port->lock);
+ return -ENODATA;
+ }
+
+ *src_pdo = kcalloc(port->nr_source_caps, sizeof(u32), GFP_KERNEL);
+ if (!src_pdo) {
+ mutex_unlock(&port->lock);
+ return -ENOMEM;
+ }
+
+ nr_pdo = tcpm_copy_pdos(*src_pdo, port->source_caps,
+ port->nr_source_caps);
+ mutex_unlock(&port->lock);
+ return nr_pdo;
+}
+EXPORT_SYMBOL_GPL(tcpm_get_partner_src_caps);
+
+void tcpm_put_partner_src_caps(u32 **src_pdo)
+{
+ kfree(*src_pdo);
+ *src_pdo = NULL;
+}
+EXPORT_SYMBOL_GPL(tcpm_put_partner_src_caps);
+
/* Power Supply access to expose source power information */
enum tcpm_psy_online_states {
TCPM_PSY_OFFLINE = 0,
diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
index 42fcfbe10590..f83d9ff89a13 100644
--- a/include/linux/usb/tcpm.h
+++ b/include/linux/usb/tcpm.h
@@ -161,5 +161,7 @@ void tcpm_pd_transmit_complete(struct tcpm_port *port,
enum tcpm_transmit_status status);
void tcpm_pd_hard_reset(struct tcpm_port *port);
void tcpm_tcpc_reset(struct tcpm_port *port);
+int tcpm_get_partner_src_caps(struct tcpm_port *port, u32 **pdo);
+void tcpm_put_partner_src_caps(u32 **pdo);

#endif /* __LINUX_USB_TCPM_H */
--
2.30.0.478.g8a0d178c01-goog


2021-02-15 17:43:33

by Dan Carpenter

[permalink] [raw]
Subject: Re: [PATCH v3] usb: typec: tcpm: Export partner Source Capabilities

Hi Kyle,

url: https://github.com/0day-ci/linux/commits/Kyle-Tso/usb-typec-tcpm-Export-partner-Source-Capabilities/20210214-192125
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: i386-randconfig-m021-20210214 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>

smatch warnings:
drivers/usb/typec/tcpm/tcpm.c:5770 tcpm_get_partner_src_caps() warn: variable dereferenced before check 'src_pdo' (see line 5769)

vim +/src_pdo +5770 drivers/usb/typec/tcpm/tcpm.c

bfd31a180a3d55 Kyle Tso 2021-02-14 5759 int tcpm_get_partner_src_caps(struct tcpm_port *port, u32 **src_pdo)
bfd31a180a3d55 Kyle Tso 2021-02-14 5760 {
bfd31a180a3d55 Kyle Tso 2021-02-14 5761 unsigned int nr_pdo;
bfd31a180a3d55 Kyle Tso 2021-02-14 5762
bfd31a180a3d55 Kyle Tso 2021-02-14 5763 mutex_lock(&port->lock);
bfd31a180a3d55 Kyle Tso 2021-02-14 5764 if (port->nr_source_caps == 0) {
bfd31a180a3d55 Kyle Tso 2021-02-14 5765 mutex_unlock(&port->lock);
bfd31a180a3d55 Kyle Tso 2021-02-14 5766 return -ENODATA;
bfd31a180a3d55 Kyle Tso 2021-02-14 5767 }
bfd31a180a3d55 Kyle Tso 2021-02-14 5768
bfd31a180a3d55 Kyle Tso 2021-02-14 @5769 *src_pdo = kcalloc(port->nr_source_caps, sizeof(u32), GFP_KERNEL);
bfd31a180a3d55 Kyle Tso 2021-02-14 @5770 if (!src_pdo) {

Typo. Missing * char.

bfd31a180a3d55 Kyle Tso 2021-02-14 5771 mutex_unlock(&port->lock);
bfd31a180a3d55 Kyle Tso 2021-02-14 5772 return -ENOMEM;
bfd31a180a3d55 Kyle Tso 2021-02-14 5773 }
bfd31a180a3d55 Kyle Tso 2021-02-14 5774
bfd31a180a3d55 Kyle Tso 2021-02-14 5775 nr_pdo = tcpm_copy_pdos(*src_pdo, port->source_caps,
bfd31a180a3d55 Kyle Tso 2021-02-14 5776 port->nr_source_caps);
bfd31a180a3d55 Kyle Tso 2021-02-14 5777 mutex_unlock(&port->lock);
bfd31a180a3d55 Kyle Tso 2021-02-14 5778 return nr_pdo;
bfd31a180a3d55 Kyle Tso 2021-02-14 5779 }

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/[email protected]


Attachments:
(No filename) (2.16 kB)
.config.gz (29.78 kB)
Download all attachments

2021-03-02 20:24:09

by Greg KH

[permalink] [raw]
Subject: Re: [PATCH v3] usb: typec: tcpm: Export partner Source Capabilities

On Sun, Feb 14, 2021 at 07:17:30PM +0800, Kyle Tso wrote:
> Export a function for other drivers to get the partner Source
> Capabilities.

What driver? We need a user of new functions in the kernel, otherwise
they are ripe for removal.

thanks,

greg k-h