path: root/drivers/usb/renesas_usbhs/fifo.c

/*
 * Renesas USB driver
 *
 * Copyright (C) 2011 Renesas Solutions Corp.
 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/scatterlist.h>
#include "./common.h"
#include "./pipe.h"

#define usbhsf_get_cfifo(p)	(&((p)->fifo_info.cfifo))
#define usbhsf_get_d0fifo(p)	(&((p)->fifo_info.d0fifo))
#define usbhsf_get_d1fifo(p)	(&((p)->fifo_info.d1fifo))
#define usbhsf_is_cfifo(p, f)	(usbhsf_get_cfifo(p) == f)

#define usbhsf_fifo_is_busy(f)	((f)->pipe) /* see usbhs_pipe_select_fifo */

/*
 *		packet initialize
 */
void usbhs_pkt_init(struct usbhs_pkt *pkt)
{
	pkt->dma = DMA_ADDR_INVALID;
	INIT_LIST_HEAD(&pkt->node);
}

/*
 *		packet control function
 */
static int usbhsf_null_handle(struct usbhs_pkt *pkt, int *is_done)
{
	struct usbhs_priv *priv = usbhs_pipe_to_priv(pkt->pipe);
	struct device *dev = usbhs_priv_to_dev(priv);

	dev_err(dev, "null handler\n");

	return -EINVAL;
}

static struct usbhs_pkt_handle usbhsf_null_handler = {
	.prepare = usbhsf_null_handle,
	.try_run = usbhsf_null_handle,
};

void usbhs_pkt_push(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt,
		    void (*done)(struct usbhs_priv *priv,
				 struct usbhs_pkt *pkt),
		    void *buf, int len, int zero, int sequence)
{
	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
	struct device *dev = usbhs_priv_to_dev(priv);
	unsigned long flags;

	if (!done) {
		dev_err(dev, "no done function\n");
		return;
	}

	/********************  spin lock ********************/
	usbhs_lock(priv, flags);

	if (!pipe->handler) {
		dev_err(dev, "no handler function\n");
		pipe->handler = &usbhsf_null_handler;
	}

	list_move_tail(&pkt->node, &pipe->list);

	/*
	 * each pkt must hold own handler.
	 * because handler might be changed by its situation.
	 * dma handler -> pio handler.
	 */
	pkt->pipe	= pipe;
	pkt->buf	= buf;
	pkt->handler	= pipe->handler;
	pkt->length	= len;
	pkt->zero	= zero;
	pkt->actual	= 0;
	pkt->done	= done;
	pkt->sequence	= sequence;

	usbhs_unlock(priv, flags);
	/********************  spin unlock ******************/
}

static void __usbhsf_pkt_del(struct usbhs_pkt *pkt)
{
	list_del_init(&pkt->node);
}

static struct usbhs_pkt *__usbhsf_pkt_get(struct usbhs_pipe *pipe)
{
	if (list_empty(&pipe->list))
		return NULL;

	return list_first_entry(&pipe->list, struct usbhs_pkt, node);
}

struct usbhs_pkt *usbhs_pkt_pop(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt)
{
	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
	unsigned long flags;

	/********************  spin lock ********************/
	usbhs_lock(priv, flags);

	if (!pkt)
		pkt = __usbhsf_pkt_get(pipe);

	if (pkt)
		__usbhsf_pkt_del(pkt);

	usbhs_unlock(priv, flags);
	/********************  spin unlock ******************/

	return pkt;
}

enum {
	USBHSF_PKT_PREPARE,
	USBHSF_PKT_TRY_RUN,
	USBHSF_PKT_DMA_DONE,
};

static int usbhsf_pkt_handler(struct usbhs_pipe *pipe, int type)
{
	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
	struct usbhs_pkt *pkt;
	struct device *dev = usbhs_priv_to_dev(priv);
	int (*func)(struct usbhs_pkt *pkt, int *is_done);
	unsigned long flags;
	int ret = 0;
	int is_done = 0;

	/********************  spin lock ********************/
	usbhs_lock(priv, flags);

	pkt = __usbhsf_pkt_get(pipe);
	if (!pkt)
		goto __usbhs_pkt_handler_end;

	switch (type) {
	case USBHSF_PKT_PREPARE:
		func = pkt->handler->prepare;
		break;
	case USBHSF_PKT_TRY_RUN:
		func = pkt->handler->try_run;
		break;
	case USBHSF_PKT_DMA_DONE:
		func = pkt->handler->dma_done;
		break;
	default:
		dev_err(dev, "unknown pkt hander\n");
		goto __usbhs_pkt_handler_end;
	}

	ret = func(pkt, &is_done);

	if (is_done)
		__usbhsf_pkt_del(pkt);

__usbhs_pkt_handler_end:
	usbhs_unlock(priv, flags);
	/********************  spin unlock ******************/

	if (is_done) {
		pkt->done(priv, pkt);
		usbhs_pkt_start(pipe);
	}

	return ret;
}

void usbhs_pkt_start(struct usbhs_pipe *pipe)
{
	usbhsf_pkt_handler(pipe, USBHSF_PKT_PREPARE);
}

/*
 *		irq enable/disable function
 */
#define usbhsf_irq_empty_ctrl(p, e) usbhsf_irq_callback_ctrl(p, bempsts, e)
#define usbhsf_irq_ready_ctrl(p, e) usbhsf_irq_callback_ctrl(p, brdysts, e)
#define usbhsf_irq_callback_ctrl(pipe, status, enable)			\
	({								\
		struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);	\
		struct usbhs_mod *mod = usbhs_mod_get_current(priv);	\
		u16 status = (1 << usbhs_pipe_number(pipe));		\
		if (!mod)						\
			return;						\
		if (enable)						\
			mod->irq_##status |= status;			\
		else							\
			mod->irq_##status &= ~status;			\
		usbhs_irq_callback_update(priv, mod);			\
	})

static void usbhsf_tx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
{
	/*
	 * And DCP pipe can NOT use "ready interrupt" for "send"
	 * it should use "empty" interrupt.
	 * see
	 *   "Operation" - "Interrupt Function" - "BRDY Interrupt"
	 *
	 * on the other hand, normal pipe can use "ready interrupt" for "send"
	 * even though it is single/double buffer
	 */
	if (usbhs_pipe_is_dcp(pipe))
		usbhsf_irq_empty_ctrl(pipe, enable);
	else
		usbhsf_irq_ready_ctrl(pipe, enable);
}

static void usbhsf_rx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
{