Merge "serial: msm_geni_serial: Do not drop port->lock in polling mode" (35a319a1) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/tty/serial/msm_geni_serial.c

+28 −40

Original line number	Diff line number	Diff line
		@@ -172,8 +172,7 @@ struct msm_geni_serial_port {
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx,
		unsigned long *flags);
		bool drop_rx);
		struct device *wrapper_dev;
		struct se_geni_rsc serial_rsc;
		dma_addr_t tx_dma;
		@@ -213,12 +212,12 @@ static int handle_rx_console(struct uart_port *uport,
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx, unsigned long *flags);
		bool drop_rx);
		static int handle_rx_hs(struct uart_port *uport,
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx, unsigned long *flags);
		bool drop_rx);
		static unsigned int msm_geni_serial_tx_empty(struct uart_port *port);
		static int msm_geni_serial_power_on(struct uart_port *uport);
		static void msm_geni_serial_power_off(struct uart_port *uport);
		@@ -238,7 +237,7 @@ static int uart_line_id;
		static struct msm_geni_serial_port msm_geni_console_port;
		static struct msm_geni_serial_port msm_geni_serial_ports[GENI_UART_NR_PORTS];
		static void msm_geni_serial_handle_isr(struct uart_port *uport,
		unsigned long *flags);
		unsigned long *flags, bool is_irq_masked);

		/*
		* The below API is required to check if uport->lock (spinlock)
		@@ -351,7 +350,6 @@ bool geni_wait_for_cmd_done(struct uart_port *uport, bool is_irq_masked)
		{
		struct msm_geni_serial_port *msm_port = GET_DEV_PORT(uport);
		unsigned long timeout = POLL_ITERATIONS;
		unsigned long ret;
		unsigned long flags = 0;

		/*
		@@ -366,13 +364,13 @@ bool geni_wait_for_cmd_done(struct uart_port *uport, bool is_irq_masked)
		*/
		if (msm_port->m_cmd) {
		while (!msm_port->m_cmd_done && timeout > 0) {
		msm_geni_serial_handle_isr(uport, &flags);
		msm_geni_serial_handle_isr(uport, &flags, true);
		timeout--;
		udelay(100);
		}
		} else if (msm_port->s_cmd) {
		while (!msm_port->s_cmd_done && timeout > 0) {
		msm_geni_serial_handle_isr(uport, &flags);
		msm_geni_serial_handle_isr(uport, &flags, true);
		timeout--;
		udelay(100);
		}
		@@ -380,16 +378,16 @@ bool geni_wait_for_cmd_done(struct uart_port *uport, bool is_irq_masked)
		} else {
		/* Waiting for 10 milli second for interrupt to be fired */
		if (msm_port->m_cmd)
		ret = wait_for_completion_timeout
		timeout = wait_for_completion_timeout
		(&msm_port->m_cmd_timeout,
		msecs_to_jiffies(POLL_WAIT_TIMEOUT_MSEC));
		else if (msm_port->s_cmd)
		ret = wait_for_completion_timeout
		timeout = wait_for_completion_timeout
		(&msm_port->s_cmd_timeout,
		msecs_to_jiffies(POLL_WAIT_TIMEOUT_MSEC));
		}

		return ret ? 0 : 1;
		return timeout ? 0 : 1;
		}

		static void msm_geni_serial_config_port(struct uart_port *uport, int cfg_flags)
		@@ -1033,13 +1031,12 @@ static int handle_rx_console(struct uart_port *uport,
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx, unsigned long *flags)
		bool drop_rx)
		{
		int i, c;
		unsigned char *rx_char;
		struct tty_port *tport;
		struct msm_geni_serial_port *msm_port = GET_DEV_PORT(uport);
		bool locked;

		tport = &uport->state->port;
		for (i = 0; i < rx_fifo_wc; i++) {
		@@ -1065,23 +1062,6 @@ static int handle_rx_console(struct uart_port *uport,
		tty_insert_flip_char(tport, rx_char[c], flag);
		}
		}
		if (!drop_rx) {
		/*
		* Driver acquiring port->lock in isr function and calling
		* tty_flip_buffer_push() which in turn will wait for
		* another lock from framework __queue_work function.
		* release the port lock before calling tty_flip_buffer_push()
		* to avoid deadlock scenarios.
		*/
		locked = msm_geni_serial_spinlocked(uport);
		if (locked) {
		spin_unlock_irqrestore(&uport->lock, *flags);
		tty_flip_buffer_push(tport);
		spin_lock_irqsave(&uport->lock, *flags);
		} else {
		tty_flip_buffer_push(tport);
		}
		}
		return 0;
		}
		#else
		@@ -1089,7 +1069,7 @@ static int handle_rx_console(struct uart_port *uport,
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx, unsigned long *flags)
		bool drop_rx)
		{
		return -EPERM;
		}
		@@ -1520,7 +1500,7 @@ static void stop_rx_sequencer(struct uart_port *uport)
		"%s cancel failed is_rx_active:%d 0x%x\n",
		__func__, is_rx_active, geni_status);
		if (uart_console(uport) && !is_rx_active) {
		msm_geni_serial_handle_isr(uport, &flags);
		msm_geni_serial_handle_isr(uport, &flags, true);
		goto exit_rx_seq;
		}
		port->s_cmd_done = false;
		@@ -1568,7 +1548,7 @@ static int handle_rx_hs(struct uart_port *uport,
		unsigned int rx_fifo_wc,
		unsigned int rx_last_byte_valid,
		unsigned int rx_last,
		bool drop_rx, unsigned long *flags)
		bool drop_rx)
		{
		unsigned char *rx_char;
		struct tty_port *tport;
		@@ -1600,8 +1580,7 @@ static int handle_rx_hs(struct uart_port *uport,
		return ret;
		}

		static int msm_geni_serial_handle_rx(struct uart_port *uport, bool drop_rx,
		unsigned long *flags)
		static int msm_geni_serial_handle_rx(struct uart_port *uport, bool drop_rx)
		{
		int ret = 0;
		unsigned int rx_fifo_status;
		@@ -1620,7 +1599,7 @@ static int msm_geni_serial_handle_rx(struct uart_port *uport, bool drop_rx,
		rx_last = rx_fifo_status & RX_LAST;
		if (rx_fifo_wc)
		ret = port->handle_rx(uport, rx_fifo_wc, rx_last_byte_valid,
		rx_last, drop_rx, flags);
		rx_last, drop_rx);
		return ret;
		}

		@@ -1803,7 +1782,8 @@ static int msm_geni_serial_handle_dma_tx(struct uart_port *uport)
		}

		static void msm_geni_serial_handle_isr(struct uart_port *uport,
		unsigned long *flags)
		unsigned long *flags,
		bool is_irq_masked)
		{
		unsigned int m_irq_status;
		unsigned int s_irq_status;
		@@ -1889,8 +1869,16 @@ static void msm_geni_serial_handle_isr(struct uart_port *uport,
		}

		if (s_irq_status & (S_RX_FIFO_WATERMARK_EN \|
		S_RX_FIFO_LAST_EN))
		msm_geni_serial_handle_rx(uport, drop_rx, flags);
		S_RX_FIFO_LAST_EN)) {
		msm_geni_serial_handle_rx(uport, drop_rx);
		if (!drop_rx && !is_irq_masked) {
		spin_unlock_irqrestore(&uport->lock, *flags);
		tty_flip_buffer_push(tport);
		spin_lock_irqsave(&uport->lock, *flags);
		} else if (!drop_rx) {
		tty_flip_buffer_push(tport);
		}
		}
		} else {
		dma_tx_status = geni_read_reg_nolog(uport->membase,
		SE_DMA_TX_IRQ_STAT);
		@@ -1984,7 +1972,7 @@ static irqreturn_t msm_geni_serial_isr(int isr, void *dev)
		unsigned long flags;

		spin_lock_irqsave(&uport->lock, flags);
		msm_geni_serial_handle_isr(uport, &flags);
		msm_geni_serial_handle_isr(uport, &flags, false);
		spin_unlock_irqrestore(&uport->lock, flags);
		return IRQ_HANDLED;
		}