[PATCH v2 4/4] USB: mxu11x0: move firmware download and endpoint testing to probe callback

From: Mathieu OTHACEHE
Date: Mon Jan 04 2016 - 13:50:44 EST


Move interrupt in endpoint test and firmware download to a new probe
callback. This avoids unnecessary memory allocations done by core
before port_probe callback is called.

If the device has to be reseted (firmware downloaded) or if the
interface is incorrect (no interrupt in endpoint), the probe fails
by returning ENODEV.

Signed-off-by: Mathieu OTHACEHE <m.othacehe@xxxxxxxxx>
---

Changes in v2:
* Remove useless paranthesis
* Fix multi-line comment

drivers/usb/serial/mxu11x0.c | 131 ++++++++++++++++++++++++++-----------------
1 file changed, 79 insertions(+), 52 deletions(-)

diff --git a/drivers/usb/serial/mxu11x0.c b/drivers/usb/serial/mxu11x0.c
index 6326cda..b942aeb 100644
--- a/drivers/usb/serial/mxu11x0.c
+++ b/drivers/usb/serial/mxu11x0.c
@@ -272,7 +272,8 @@ static int mxu1_send_ctrl_urb(struct usb_serial *serial,
}

static int mxu1_download_firmware(struct usb_serial *serial,
- const struct firmware *fw_p)
+ const struct firmware *fw_p,
+ struct usb_endpoint_descriptor *endpoint)
{
int status = 0;
int buffer_size;
@@ -285,7 +286,7 @@ static int mxu1_download_firmware(struct usb_serial *serial,
struct mxu1_firmware_header *header;
unsigned int pipe;

- pipe = usb_sndbulkpipe(dev, serial->port[0]->bulk_out_endpointAddress);
+ pipe = usb_sndbulkpipe(dev, endpoint->bEndpointAddress);

buffer_size = fw_p->size + sizeof(*header);
buffer = kmalloc(buffer_size, GFP_KERNEL);
@@ -328,16 +329,86 @@ static int mxu1_download_firmware(struct usb_serial *serial,
return 0;
}

-static int mxu1_port_probe(struct usb_serial_port *port)
+static int mxu1_probe(struct usb_serial *serial, const struct usb_device_id *id)
{
- struct mxu1_port *mxport;
- struct mxu1_device *mxdev;
+ struct usb_host_interface *cur_altsetting;
+ char fw_name[32];
+ const struct firmware *fw_p = NULL;
+ struct usb_device *dev = serial->dev;
+ u16 model;
+ int err;
+ struct usb_endpoint_descriptor *endpoint, *interrupt_in, *bulk_out;
+ int i;
+
+ dev_dbg(&serial->interface->dev, "%s - product 0x%04X, num configurations %d, configuration value %d\n",
+ __func__, le16_to_cpu(dev->descriptor.idProduct),
+ dev->descriptor.bNumConfigurations,
+ dev->actconfig->desc.bConfigurationValue);
+
+ cur_altsetting = serial->interface->cur_altsetting;
+ interrupt_in = NULL;
+ bulk_out = NULL;
+
+ for (i = 0; i < cur_altsetting->desc.bNumEndpoints; i++) {
+ endpoint = &cur_altsetting->endpoint[i].desc;
+ if (usb_endpoint_is_bulk_out(endpoint)) {
+ dev_dbg(&serial->interface->dev,
+ "found bulk out on endpoint %d\n", i);
+ bulk_out = endpoint;
+ }
+
+ if (usb_endpoint_is_int_in(endpoint)) {
+ dev_dbg(&serial->interface->dev,
+ "found interrupt in on endpoint %d\n", i);
+ interrupt_in = endpoint;
+ }
+ }
+
+ /* if we have only 1 bulk out endpoint, download firmware */
+ if (bulk_out && cur_altsetting->desc.bNumEndpoints == 1) {
+
+ model = le16_to_cpu(dev->descriptor.idProduct);
+ snprintf(fw_name,
+ sizeof(fw_name),
+ "moxa/moxa-%04x.fw",
+ model);
+
+ err = request_firmware(&fw_p, fw_name, &serial->interface->dev);
+ if (err) {
+ dev_err(&serial->interface->dev, "failed to request firmware: %d\n",
+ err);
+ return -ENODEV;
+ }
+
+ err = mxu1_download_firmware(serial, fw_p, bulk_out);
+ if (err)
+ goto err_release_firmware;

- if (!port->interrupt_in_urb) {
- dev_err(&port->dev, "no interrupt urb\n");
+ /* device is being reset */
+ err = -ENODEV;
+ goto err_release_firmware;
+
+ } else if (!interrupt_in) {
+ /*
+ * firmware is already loaded but there is
+ * no interrupt in endpoint available
+ */
+ dev_err(&serial->interface->dev, "no interrupt endpoint\n");
return -ENODEV;
}

+ return 0;
+
+err_release_firmware:
+ release_firmware(fw_p);
+ return err;
+}
+
+static int mxu1_port_probe(struct usb_serial_port *port)
+{
+ struct mxu1_port *mxport;
+ struct mxu1_device *mxdev;
+
mxport = kzalloc(sizeof(struct mxu1_port), GFP_KERNEL);
if (!mxport)
return -ENOMEM;
@@ -381,16 +452,6 @@ static int mxu1_port_remove(struct usb_serial_port *port)
static int mxu1_startup(struct usb_serial *serial)
{
struct mxu1_device *mxdev;
- struct usb_device *dev = serial->dev;
- struct usb_host_interface *cur_altsetting;
- char fw_name[32];
- const struct firmware *fw_p = NULL;
- int err;
-
- dev_dbg(&serial->interface->dev, "%s - product 0x%04X, num configurations %d, configuration value %d\n",
- __func__, le16_to_cpu(dev->descriptor.idProduct),
- dev->descriptor.bNumConfigurations,
- dev->actconfig->desc.bConfigurationValue);

/* create device structure */
mxdev = kzalloc(sizeof(struct mxu1_device), GFP_KERNEL);
@@ -399,42 +460,7 @@ static int mxu1_startup(struct usb_serial *serial)

usb_set_serial_data(serial, mxdev);

- mxdev->mxd_model = le16_to_cpu(dev->descriptor.idProduct);
-
- cur_altsetting = serial->interface->cur_altsetting;
-
- /* if we have only 1 configuration, download firmware */
- if (cur_altsetting->desc.bNumEndpoints == 1) {
-
- snprintf(fw_name,
- sizeof(fw_name),
- "moxa/moxa-%04x.fw",
- mxdev->mxd_model);
-
- err = request_firmware(&fw_p, fw_name, &serial->interface->dev);
- if (err) {
- dev_err(&serial->interface->dev, "failed to request firmware: %d\n",
- err);
- goto err_free_mxdev;
- }
-
- err = mxu1_download_firmware(serial, fw_p);
- if (err)
- goto err_release_firmware;
-
- /* device is being reset */
- err = -ENODEV;
- goto err_release_firmware;
- }
-
return 0;
-
-err_release_firmware:
- release_firmware(fw_p);
-err_free_mxdev:
- kfree(mxdev);
-
- return err;
}

static void mxu1_release(struct usb_serial *serial)
@@ -964,6 +990,7 @@ static struct usb_serial_driver mxu11x0_device = {
.description = "MOXA UPort 11x0",
.id_table = mxu1_idtable,
.num_ports = 1,
+ .probe = mxu1_probe,
.port_probe = mxu1_port_probe,
.port_remove = mxu1_port_remove,
.attach = mxu1_startup,
--
2.6.4

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