From: Fabio Estevam <fabio.estevam@xxxxxxx>
Commit 0d6fce904452 ("tty: serial: lpuart: introduce lpuart_soc_data to
represent SoC property") introduced a buggy logic for detecting the 32-bit
type UART since the condition: "if (sport->port.iotype & UPIO_MEM32BE)"
is always true.
Performing such bitfield AND operation is not correct, because in the
case of Vybrid UART iotype is UPIO_MEM (2), so:
UPIO_MEM & UPIO_MEM32BE = 010 & 110 = 010, which is true.
Such logic tells the driver to always treat the UART operations as 32-bit,
leading to the driver misbehavior on Vybrid.
Fix the 32-bit type detection logic to avoid UART breakage on Vybrid.
While at it, introduce a lpuart_is_32() function to help readability.
Fixes: 0d6fce904452 ("tty: serial: lpuart: introduce lpuart_soc_data to represent SoC property")
Reported-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Fabio Estevam <fabio.estevam@xxxxxxx>
---
drivers/tty/serial/fsl_lpuart.c | 24 +++++++++++++++---------
1 file changed, 15 insertions(+), 9 deletions(-)
diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 343de8c..898dcb0 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -619,6 +619,12 @@ static unsigned int lpuart32_tx_empty(struct uart_port *port)
TIOCSER_TEMT : 0;
}
+static bool lpuart_is_32(struct lpuart_port *sport)
+{
+ return sport->port.iotype == UPIO_MEM32 ||
+ sport->port.iotype == UPIO_MEM32BE;
+}
+
static irqreturn_t lpuart_txint(int irq, void *dev_id)
{
struct lpuart_port *sport = dev_id;
@@ -627,7 +633,7 @@ static irqreturn_t lpuart_txint(int irq, void *dev_id)
spin_lock_irqsave(&sport->port.lock, flags);
if (sport->port.x_char) {
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
else
writeb(sport->port.x_char, sport->port.membase + UARTDR);
@@ -635,14 +641,14 @@ static irqreturn_t lpuart_txint(int irq, void *dev_id)
}
if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) {
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart32_stop_tx(&sport->port);
else
lpuart_stop_tx(&sport->port);
goto out;
}
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart32_transmit_buffer(sport);
else
lpuart_transmit_buffer(sport);
@@ -1978,12 +1984,12 @@ static int __init lpuart_console_setup(struct console *co, char *options)
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
else
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart32_console_get_options(sport, &baud, &parity, &bits);
else
lpuart_console_get_options(sport, &baud, &parity, &bits);
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart32_setup_watermark(sport);
else
lpuart_setup_watermark(sport);
@@ -2118,7 +2124,7 @@ static int lpuart_probe(struct platform_device *pdev)
}
sport->port.irq = ret;
sport->port.iotype = sdata->iotype;
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
sport->port.ops = &lpuart32_pops;
else
sport->port.ops = &lpuart_pops;
@@ -2145,7 +2151,7 @@ static int lpuart_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, &sport->port);
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE))
+ if (lpuart_is_32(sport))
lpuart_reg.cons = LPUART32_CONSOLE;
else
lpuart_reg.cons = LPUART_CONSOLE;
@@ -2198,7 +2204,7 @@ static int lpuart_suspend(struct device *dev)
struct lpuart_port *sport = dev_get_drvdata(dev);
unsigned long temp;
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
+ if (lpuart_is_32(sport)) {
/* disable Rx/Tx and interrupts */
temp = lpuart32_read(&sport->port, UARTCTRL);
temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
@@ -2249,7 +2255,7 @@ static int lpuart_resume(struct device *dev)
if (sport->port.suspended && !sport->port.irq_wake)
clk_prepare_enable(sport->clk);
- if (sport->port.iotype & (UPIO_MEM32 | UPIO_MEM32BE)) {
+ if (lpuart_is_32(sport)) {
lpuart32_setup_watermark(sport);
temp = lpuart32_read(&sport->port, UARTCTRL);
temp |= (UARTCTRL_RIE | UARTCTRL_TIE | UARTCTRL_RE |
--
2.7.4
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