Re: [PATCH v4 2/2] usb: gadget: Add xilinx usb2 device support

[Varka Bhadram]

On 07/22/2014 02:38 PM, Subbaraya Sundeep Bhatta wrote:
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/dma-mapping.h>
> +#include "gadget_chips.h"
> +#include <linux/interrupt.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/prefetch.h>
> +#include <linux/usb/ch9.h>
> +#include <linux/usb/gadget.h>
> +

Normally we will put the includes in alphabetical because it looks good
and readable.

But we have to include the local headers separately after all the main includes...
#include <linux/delay.h>
#include <linux/device.h>
....
#include <linux/usb/gadget.h>

#include "gadget_chips.h"

(...)

> +	switch (udc->setupseqtx) {
> +	case STATUS_PHASE:
> +		switch (udc->setup.bRequest) {
> +		case USB_REQ_SET_ADDRESS:
> +			/* Set the address of the device.*/
> +			udc->write_fn(udc->base_address,
> +					XUSB_ADDRESS_OFFSET,
> +					udc->setup.wValue);

Should match open parenthesis

udc->write_fn(udc->base_address,
	      XUSB_ADDRESS_OFFSET,
	      udc->setup.wValue);


> +			break;
> +		case USB_REQ_SET_FEATURE:
> +			if (udc->setup.bRequestType ==
> +					USB_RECIP_DEVICE) {
> +				if (udc->setup.wValue ==
> +						USB_DEVICE_TEST_MODE)
> +					udc->write_fn(udc->base_address,
> +							XUSB_TESTMODE_OFFSET,
> +							test_mode);

Dto

> +			}
> +			break;
> +		}
> +		req->usb_req.actual = req->usb_req.length;
> +		xudc_done(ep0, req, 0);
> +		break;
> +	case DATA_PHASE:
> +		if (!bytes_to_tx) {
> +			/*
> +			 * We're done with data transfer, next
> +			 * will be zero length OUT with data toggle of
> +			 * 1. Setup data_toggle.
> +			 */
> +			epcfgreg = udc->read_fn(udc->base_address +
> +					ep0->offset);
> +			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
> +			udc->write_fn(udc->base_address, ep0->offset, epcfgreg);
> +			udc->setupseqtx = STATUS_PHASE;
> +		} else {
> +			length = count = min_t(u32, bytes_to_tx,
> +						EP0_MAX_PACKET);
> +			/* Copy the data to be transmitted into the DPRAM. */
> +			ep0rambase = (u8 __force *) (udc->base_address +
> +					(ep0->rambase << 2));
> +
> +			buffer = req->usb_req.buf + req->usb_req.actual;
> +			req->usb_req.actual = req->usb_req.actual + length;
> +			memcpy((void *)ep0rambase, buffer, length);
> +		}
> +		udc->write_fn(udc->base_address, XUSB_EP_BUF0COUNT_OFFSET,
> +				count);
> +		udc->write_fn(udc->base_address, XUSB_BUFFREADY_OFFSET, 1);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +/**
> + * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
> + * @udc: pointer to the udc structure.
> + * @intrstatus:	It's the mask value for the interrupt sources on endpoint 0.
> + *
> + * Processes the commands received during enumeration phase.
> + */
> +static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
> +{
> +
> +	if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
> +		xudc_handle_setup(udc);
> +	} else {
> +		if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
> +			xudc_ep0_out(udc);
> +		else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
> +			xudc_ep0_in(udc);
> +	}
> +}
> +
> +/**
> + * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
> + * @udc: pointer to the udc structure.
> + * @epnum: End point number for which the interrupt is to be processed
> + * @intrstatus:	mask value for interrupt sources of endpoints other
> + *		than endpoint 0.
> + *
> + * Processes the buffer completion interrupts.
> + */
> +static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
> +		u32 intrstatus)

Should match open parenthesis:

static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
				    u32 intrstatus)

> +{
> +
> +	struct xusb_req *req;
> +	struct xusb_ep *ep;
> +
> +	ep = &udc->ep[epnum];
> +	/* Process the End point interrupts.*/
> +	if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
> +		ep->buffer0ready = 0;
> +	if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
> +		ep->buffer1ready = 0;
> +
> +	if (list_empty(&ep->queue))
> +		return;
> +
> +	req = list_first_entry(&ep->queue, struct xusb_req, queue);
> +
> +	if (ep->is_in)
> +		xudc_write_fifo(ep, req);
> +	else
> +		xudc_read_fifo(ep, req);
> +}
> +

(...)

> +
> +	/* buffer for data of get_status request */
> +	buff = kzalloc(2, GFP_KERNEL);

define proper macro for '2'. Also we can use devm_kzalloc().

Also one more thing: if we use kzalloc for allocating the 2 bytes
no where i found that releasing the buffer on error path.

> +	if (buff == NULL) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +	/* Dummy request ready, free this in remove */
> +	udc->req->usb_req.buf = buff;
> +
> +	/* Set device address to 0.*/
> +	udc->write_fn(udc->base_address, XUSB_ADDRESS_OFFSET, 0);
> +
> +	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
> +	if (ret)
> +		goto fail;

If it fails we have to free the buff. see above..

> +
> +	udc->dev = &udc->gadget.dev;
> +
> +	/* Enable the interrupts.*/
> +	ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
> +		XUSB_STATUS_FIFO_BUFF_RDY_MASK |
> +		XUSB_STATUS_FIFO_BUFF_FREE_MASK |
> +		XUSB_STATUS_SETUP_PACKET_MASK |
> +		XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
> +
> +	udc->write_fn(udc->base_address, XUSB_IER_OFFSET, ier);
> +
> +	platform_set_drvdata(pdev, udc);
> +
> +	dev_dbg(&pdev->dev, "%s at 0x%08X mapped to 0x%08X %s\n",
> +		driver_name, (u32)res->start,
> +		(u32 __force)udc->base_address,
> +		udc->dma_enabled ? "with DMA" : "without DMA");
> +
> +	return 0;
> +fail:
> +	dev_err(&pdev->dev, "probe failed, %d\n", ret);
> +	return ret;
> +}
> +
> +/**
> + * xudc_remove - Releases the resources allocated during the initialization.
> + * @pdev: pointer to the platform device structure.
> + *
> + * Return: 0 always
> + */
> +static int xudc_remove(struct platform_device *pdev)
> +{
> +	struct xusb_udc *udc = platform_get_drvdata(pdev);
> +	void *buf = udc->req->usb_req.buf;

No need of creating another "void *". We can directly free it. (It is u8 *)

> +
> +	usb_del_gadget_udc(&udc->gadget);
> +
> +	/* free memory allocated for dummy request buffer */
> +	kfree(buf);
> +	/* free memory allocated for dummy request */
> +	kfree(udc->req);
> +
> +	return 0;
> +}
> +
> +/* Match table for of_platform binding */
> +static const struct of_device_id usb_of_match[] = {
> +	{ .compatible = "xlnx,usb2-device-4.00.a", },
> +	{ /* end of list */ },
> +};
> +MODULE_DEVICE_TABLE(of, usb_of_match);
> +
> +static struct platform_driver xudc_driver = {
> +	.driver = {
> +		.name = driver_name,
> +		.owner = THIS_MODULE,

We can drop the owner field update... It updated automatically
by module_platform_driver().


Please run checkpatch.pl on this patch. You may get more warnings and errors.


--
Regards,
Varka Bhadram.

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