[PATCH] Char: isicom, eliminate spinlock recursion (cfe7c09a) · Commits · e / devices / android_kernel_oneplus_sm7250

drivers/char/isicom.c

+51 −52

Original line number	Original line	Diff line number	Diff line
	@@ -230,6 +230,20 @@ static struct isi_port isi_ports[PORT_COUNT];
	* it wants to talk.		* it wants to talk.
	*/		*/

			static inline int WaitTillCardIsFree(u16 base)
			{
			unsigned int count = 0;
			unsigned int a = in_atomic(); /* do we run under spinlock? */

			while (!(inw(base + 0xe) & 0x1) && count++ < 100)
			if (a)
			mdelay(1);
			else
			msleep(1);

			return !(inw(base + 0xe) & 0x1);
			}

	static int lock_card(struct isi_board *card)		static int lock_card(struct isi_board *card)
	{		{
	char retries;		char retries;
	@@ -276,69 +290,71 @@ static void unlock_card(struct isi_board *card)
	* ISI Card specific ops ...		* ISI Card specific ops ...
	*/		*/

			/* card->lock HAS to be held */
	static void raise_dtr(struct isi_port *port)		static void raise_dtr(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	unsigned long base = card->base;		unsigned long base = card->base;
	u16 channel = port->channel;		u16 channel = port->channel;

	if (!lock_card(card))		if (WaitTillCardIsFree(base))
	return;		return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);		outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw(0x0504, base);		outw(0x0504, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	port->status \|= ISI_DTR;		port->status \|= ISI_DTR;
	unlock_card(card);
	}		}

			/* card->lock HAS to be held */
	static inline void drop_dtr(struct isi_port *port)		static inline void drop_dtr(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	unsigned long base = card->base;		unsigned long base = card->base;
	u16 channel = port->channel;		u16 channel = port->channel;

	if (!lock_card(card))		if (WaitTillCardIsFree(base))
	return;		return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);		outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw(0x0404, base);		outw(0x0404, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	port->status &= ~ISI_DTR;		port->status &= ~ISI_DTR;
	unlock_card(card);
	}		}

			/* card->lock HAS to be held */
	static inline void raise_rts(struct isi_port *port)		static inline void raise_rts(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	unsigned long base = card->base;		unsigned long base = card->base;
	u16 channel = port->channel;		u16 channel = port->channel;

	if (!lock_card(card))		if (WaitTillCardIsFree(base))
	return;		return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);		outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw(0x0a04, base);		outw(0x0a04, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	port->status \|= ISI_RTS;		port->status \|= ISI_RTS;
	unlock_card(card);
	}		}

			/* card->lock HAS to be held */
	static inline void drop_rts(struct isi_port *port)		static inline void drop_rts(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	unsigned long base = card->base;		unsigned long base = card->base;
	u16 channel = port->channel;		u16 channel = port->channel;

	if (!lock_card(card))		if (WaitTillCardIsFree(base))
	return;		return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);		outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw(0x0804, base);		outw(0x0804, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	port->status &= ~ISI_RTS;		port->status &= ~ISI_RTS;
	unlock_card(card);
	}		}

			/* card->lock MUST NOT be held */
	static inline void raise_dtr_rts(struct isi_port *port)		static inline void raise_dtr_rts(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	@@ -355,35 +371,20 @@ static inline void raise_dtr_rts(struct isi_port *port)
	unlock_card(card);		unlock_card(card);
	}		}

			/* card->lock HAS to be held */
	static void drop_dtr_rts(struct isi_port *port)		static void drop_dtr_rts(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	unsigned long base = card->base;		unsigned long base = card->base;
	u16 channel = port->channel;		u16 channel = port->channel;

	if (!lock_card(card))		if (WaitTillCardIsFree(base))
	return;		return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);		outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw(0x0c04, base);		outw(0x0c04, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	port->status &= ~(ISI_RTS \| ISI_DTR);		port->status &= ~(ISI_RTS \| ISI_DTR);
	unlock_card(card);
	}

	static inline void kill_queue(struct isi_port *port, short queue)
	{
	struct isi_board *card = port->card;
	unsigned long base = card->base;
	u16 channel = port->channel;

	if (!lock_card(card))
	return;

	outw(0x8000 \| (channel << card->shift_count) \| 0x02, base);
	outw((queue << 8) \| 0x06, base);
	InterruptTheCard(base);
	unlock_card(card);
	}		}

	/*		/*
	@@ -744,7 +745,7 @@ static void isicom_config_port(struct isi_port *port)
	else		else
	raise_dtr(port);		raise_dtr(port);

	if (lock_card(card)) {		if (WaitTillCardIsFree(base) == 0) {
	outw(0x8000 \| (channel << shift_count) \|0x03, base);		outw(0x8000 \| (channel << shift_count) \|0x03, base);
	outw(linuxb_to_isib[baud] << 8 \| 0x03, base);		outw(linuxb_to_isib[baud] << 8 \| 0x03, base);
	channel_setup = 0;		channel_setup = 0;
	@@ -772,7 +773,6 @@ static void isicom_config_port(struct isi_port *port)
	}		}
	outw(channel_setup, base);		outw(channel_setup, base);
	InterruptTheCard(base);		InterruptTheCard(base);
	unlock_card(card);
	}		}
	if (C_CLOCAL(tty))		if (C_CLOCAL(tty))
	port->flags &= ~ASYNC_CHECK_CD;		port->flags &= ~ASYNC_CHECK_CD;
	@@ -791,12 +791,11 @@ static void isicom_config_port(struct isi_port *port)
	if (I_IXOFF(tty))		if (I_IXOFF(tty))
	flow_ctrl \|= ISICOM_INITIATE_XONXOFF;		flow_ctrl \|= ISICOM_INITIATE_XONXOFF;

	if (lock_card(card)) {		if (WaitTillCardIsFree(base) == 0) {
	outw(0x8000 \| (channel << shift_count) \|0x04, base);		outw(0x8000 \| (channel << shift_count) \|0x04, base);
	outw(flow_ctrl << 8 \| 0x05, base);		outw(flow_ctrl << 8 \| 0x05, base);
	outw((STOP_CHAR(tty)) << 8 \| (START_CHAR(tty)), base);		outw((STOP_CHAR(tty)) << 8 \| (START_CHAR(tty)), base);
	InterruptTheCard(base);		InterruptTheCard(base);
	unlock_card(card);
	}		}

	/* rx enabled -> enable port for rx on the card */		/* rx enabled -> enable port for rx on the card */
	@@ -821,10 +820,9 @@ static inline void isicom_setup_board(struct isi_board *bp)
	}		}
	port = bp->ports;		port = bp->ports;
	bp->status \|= BOARD_ACTIVE;		bp->status \|= BOARD_ACTIVE;
	spin_unlock_irqrestore(&bp->card_lock, flags);
	for (channel = 0; channel < bp->port_count; channel++, port++)		for (channel = 0; channel < bp->port_count; channel++, port++)
	drop_dtr_rts(port);		drop_dtr_rts(port);
	return;		spin_unlock_irqrestore(&bp->card_lock, flags);
	}		}

	static int isicom_setup_port(struct isi_port *port)		static int isicom_setup_port(struct isi_port *port)
	@@ -857,7 +855,12 @@ static int isicom_setup_port(struct isi_port *port)
	port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;		port->xmit_cnt = port->xmit_head = port->xmit_tail = 0;

	/* discard any residual data */		/* discard any residual data */
	kill_queue(port, ISICOM_KILLTX \| ISICOM_KILLRX);		if (WaitTillCardIsFree(card->base) == 0) {
			outw(0x8000 \| (port->channel << card->shift_count) \| 0x02,
			card->base);
			outw(((ISICOM_KILLTX \| ISICOM_KILLRX) << 8) \| 0x06, card->base);
			InterruptTheCard(card->base);
			}

	isicom_config_port(port);		isicom_config_port(port);
	port->flags \|= ASYNC_INITIALIZED;		port->flags \|= ASYNC_INITIALIZED;
	@@ -983,28 +986,22 @@ static int isicom_open(struct tty_struct tty, struct file filp)

	static inline void isicom_shutdown_board(struct isi_board *bp)		static inline void isicom_shutdown_board(struct isi_board *bp)
	{		{
	unsigned long flags;

	spin_lock_irqsave(&bp->card_lock, flags);
	if (bp->status & BOARD_ACTIVE) {		if (bp->status & BOARD_ACTIVE) {
	bp->status &= ~BOARD_ACTIVE;		bp->status &= ~BOARD_ACTIVE;
	}		}
	spin_unlock_irqrestore(&bp->card_lock, flags);
	}		}

			/* card->lock HAS to be held */
	static void isicom_shutdown_port(struct isi_port *port)		static void isicom_shutdown_port(struct isi_port *port)
	{		{
	struct isi_board *card = port->card;		struct isi_board *card = port->card;
	struct tty_struct *tty;		struct tty_struct *tty;
	unsigned long flags;

	tty = port->tty;		tty = port->tty;

	spin_lock_irqsave(&card->card_lock, flags);		if (!(port->flags & ASYNC_INITIALIZED))
	if (!(port->flags & ASYNC_INITIALIZED)) {
	spin_unlock_irqrestore(&card->card_lock, flags);
	return;		return;
	}
	if (port->xmit_buf) {		if (port->xmit_buf) {
	free_page((unsigned long) port->xmit_buf);		free_page((unsigned long) port->xmit_buf);
	port->xmit_buf = NULL;		port->xmit_buf = NULL;
	@@ -1012,7 +1009,6 @@ static void isicom_shutdown_port(struct isi_port *port)
	port->flags &= ~ASYNC_INITIALIZED;		port->flags &= ~ASYNC_INITIALIZED;
	/* 3rd October 2000 : Vinayak P Risbud */		/* 3rd October 2000 : Vinayak P Risbud */
	port->tty = NULL;		port->tty = NULL;
	spin_unlock_irqrestore(&card->card_lock, flags);

	/*Fix done by Anil .S on 30-04-2001		/*Fix done by Anil .S on 30-04-2001
	remote login through isi port has dtr toggle problem		remote login through isi port has dtr toggle problem
	@@ -1258,10 +1254,12 @@ static int isicom_tiocmset(struct tty_struct tty, struct file file,
	unsigned int set, unsigned int clear)		unsigned int set, unsigned int clear)
	{		{
	struct isi_port *port = tty->driver_data;		struct isi_port *port = tty->driver_data;
			unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))		if (isicom_paranoia_check(port, tty->name, "isicom_ioctl"))
	return -ENODEV;		return -ENODEV;

			spin_lock_irqsave(&port->card->card_lock, flags);
	if (set & TIOCM_RTS)		if (set & TIOCM_RTS)
	raise_rts(port);		raise_rts(port);
	if (set & TIOCM_DTR)		if (set & TIOCM_DTR)
	@@ -1271,6 +1269,7 @@ static int isicom_tiocmset(struct tty_struct tty, struct file file,
	drop_rts(port);		drop_rts(port);
	if (clear & TIOCM_DTR)		if (clear & TIOCM_DTR)
	drop_dtr(port);		drop_dtr(port);
			spin_unlock_irqrestore(&port->card->card_lock, flags);

	return 0;		return 0;
	}		}
	@@ -1303,7 +1302,10 @@ static int isicom_set_serial_info(struct isi_port *port,
	(newinfo.flags & ASYNC_FLAGS));		(newinfo.flags & ASYNC_FLAGS));
	}		}
	if (reconfig_port) {		if (reconfig_port) {
			unsigned long flags;
			spin_lock_irqsave(&port->card->card_lock, flags);
	isicom_config_port(port);		isicom_config_port(port);
			spin_unlock_irqrestore(&port->card->card_lock, flags);
	}		}
	return 0;		return 0;
	}		}
	@@ -1384,6 +1386,7 @@ static void isicom_set_termios(struct tty_struct *tty,
	struct ktermios *old_termios)		struct ktermios *old_termios)
	{		{
	struct isi_port *port = tty->driver_data;		struct isi_port *port = tty->driver_data;
			unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_set_termios"))		if (isicom_paranoia_check(port, tty->name, "isicom_set_termios"))
	return;		return;
	@@ -1392,7 +1395,9 @@ static void isicom_set_termios(struct tty_struct *tty,
	tty->termios->c_iflag == old_termios->c_iflag)		tty->termios->c_iflag == old_termios->c_iflag)
	return;		return;

			spin_lock_irqsave(&port->card->card_lock, flags);
	isicom_config_port(port);		isicom_config_port(port);
			spin_unlock_irqrestore(&port->card->card_lock, flags);

	if ((old_termios->c_cflag & CRTSCTS) &&		if ((old_termios->c_cflag & CRTSCTS) &&
	!(tty->termios->c_cflag & CRTSCTS)) {		!(tty->termios->c_cflag & CRTSCTS)) {
	@@ -1469,11 +1474,15 @@ static void do_isicom_hangup(struct work_struct *work)
	static void isicom_hangup(struct tty_struct *tty)		static void isicom_hangup(struct tty_struct *tty)
	{		{
	struct isi_port *port = tty->driver_data;		struct isi_port *port = tty->driver_data;
			unsigned long flags;

	if (isicom_paranoia_check(port, tty->name, "isicom_hangup"))		if (isicom_paranoia_check(port, tty->name, "isicom_hangup"))
	return;		return;

			spin_lock_irqsave(&port->card->card_lock, flags);
	isicom_shutdown_port(port);		isicom_shutdown_port(port);
			spin_unlock_irqrestore(&port->card->card_lock, flags);

	port->count = 0;		port->count = 0;
	port->flags &= ~ASYNC_NORMAL_ACTIVE;		port->flags &= ~ASYNC_NORMAL_ACTIVE;
	port->tty = NULL;		port->tty = NULL;
	@@ -1578,16 +1587,6 @@ static int __devinit reset_card(struct pci_dev *pdev,
	return retval;		return retval;
	}		}

	static inline int WaitTillCardIsFree(u16 base)
	{
	unsigned long count = 0;

	while (!(inw(base + 0xe) & 0x1) && count++ < 100)
	msleep(5);

	return !(inw(base + 0xe) & 0x1);
	}

	static int __devinit load_firmware(struct pci_dev *pdev,		static int __devinit load_firmware(struct pci_dev *pdev,
	const unsigned int index, const unsigned int signature)		const unsigned int index, const unsigned int signature)
	{		{