[PATCH v4 3/6] tty: serial: amba-pl011: cleanup driver

From: Théo Lebrun
Date: Thu Nov 23 2023 - 08:43:17 EST


Follow recommandations from:

$ ./scripts/checkpatch.pl --strict --file \
drivers/tty/serial/amba-pl011.c

It does NOT fix alerts relative to TIOCMBIT which will be dealt with in
another patch. Fixes following alerts:

CHECK: Alignment should match open parenthesis
CHECK: Blank lines aren't necessary after an open brace '{'
CHECK: Comparison to NULL could be written [...]
CHECK: Lines should not end with a '('
CHECK: Please don't use multiple blank lines
CHECK: Please use a blank line after function/struct/union/enum declarations
CHECK: Prefer using the BIT macro
CHECK: Unbalanced braces around else statement
CHECK: Unnecessary parentheses around [...]
CHECK: braces {} should be used on all arms of this statement
CHECK: spaces preferred around that '/' (ctx:VxV)
CHECK: spaces preferred around that '|' (ctx:VxV)
ERROR: do not initialise statics to false
WARNING: Comparisons should place the constant on the right side of the test
WARNING: Possible unnecessary 'out of memory' message
WARNING: Prefer 'unsigned int' to bare use of 'unsigned'
WARNING: Prefer [subsystem eg: netdev]_info([subsystem]dev, ... then dev_info(dev, ... then pr_info(... to printk(KERN_INFO ...
WARNING: quoted string split across lines

Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Signed-off-by: Théo Lebrun <theo.lebrun@xxxxxxxxxxx>
---
drivers/tty/serial/amba-pl011.c | 147 +++++++++++++++++++---------------------
1 file changed, 71 insertions(+), 76 deletions(-)

diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index 3dc9b0fcab1c..3beac358909f 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -50,8 +50,8 @@

#define AMBA_ISR_PASS_LIMIT 256

-#define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE)
-#define UART_DUMMY_DR_RX (1 << 16)
+#define UART_DR_ERROR (UART011_DR_OE | UART011_DR_BE | UART011_DR_PE | UART011_DR_FE)
+#define UART_DUMMY_DR_RX BIT(16)

enum {
REG_DR,
@@ -125,7 +125,7 @@ static unsigned int get_fifosize_arm(struct amba_device *dev)

static struct vendor_data vendor_arm = {
.reg_offset = pl011_std_offsets,
- .ifls = UART011_IFLS_RX4_8|UART011_IFLS_TX4_8,
+ .ifls = UART011_IFLS_RX4_8 | UART011_IFLS_TX4_8,
.fr_busy = UART01x_FR_BUSY,
.fr_dsr = UART01x_FR_DSR,
.fr_cts = UART01x_FR_CTS,
@@ -203,7 +203,7 @@ static unsigned int get_fifosize_st(struct amba_device *dev)

static struct vendor_data vendor_st = {
.reg_offset = pl011_st_offsets,
- .ifls = UART011_IFLS_RX_HALF|UART011_IFLS_TX_HALF,
+ .ifls = UART011_IFLS_RX_HALF | UART011_IFLS_TX_HALF,
.fr_busy = UART01x_FR_BUSY,
.fr_dsr = UART01x_FR_DSR,
.fr_cts = UART01x_FR_CTS,
@@ -275,13 +275,13 @@ struct uart_amba_port {
static unsigned int pl011_tx_empty(struct uart_port *port);

static unsigned int pl011_reg_to_offset(const struct uart_amba_port *uap,
- unsigned int reg)
+ unsigned int reg)
{
return uap->reg_offset[reg];
}

static unsigned int pl011_read(const struct uart_amba_port *uap,
- unsigned int reg)
+ unsigned int reg)
{
void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg);

@@ -290,7 +290,7 @@ static unsigned int pl011_read(const struct uart_amba_port *uap,
}

static void pl011_write(unsigned int val, const struct uart_amba_port *uap,
- unsigned int reg)
+ unsigned int reg)
{
void __iomem *addr = uap->port.membase + pl011_reg_to_offset(uap, reg);

@@ -328,10 +328,12 @@ static int pl011_fifo_to_tty(struct uart_amba_port *uap)
uap->port.icount.brk++;
if (uart_handle_break(&uap->port))
continue;
- } else if (ch & UART011_DR_PE)
+ } else if (ch & UART011_DR_PE) {
uap->port.icount.parity++;
- else if (ch & UART011_DR_FE)
+ } else if (ch & UART011_DR_FE) {
uap->port.icount.frame++;
+ }
+
if (ch & UART011_DR_OE)
uap->port.icount.overrun++;

@@ -356,7 +358,6 @@ static int pl011_fifo_to_tty(struct uart_amba_port *uap)
return fifotaken;
}

-
/*
* All the DMA operation mode stuff goes inside this ifdef.
* This assumes that you have a generic DMA device interface,
@@ -367,18 +368,18 @@ static int pl011_fifo_to_tty(struct uart_amba_port *uap)
#define PL011_DMA_BUFFER_SIZE PAGE_SIZE

static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg,
- enum dma_data_direction dir)
+ enum dma_data_direction dir)
{
dma_addr_t dma_addr;

sg->buf = dma_alloc_coherent(chan->device->dev,
- PL011_DMA_BUFFER_SIZE, &dma_addr, GFP_KERNEL);
+ PL011_DMA_BUFFER_SIZE, &dma_addr, GFP_KERNEL);
if (!sg->buf)
return -ENOMEM;

sg_init_table(&sg->sg, 1);
sg_set_page(&sg->sg, phys_to_page(dma_addr),
- PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr));
+ PL011_DMA_BUFFER_SIZE, offset_in_page(dma_addr));
sg_dma_address(&sg->sg) = dma_addr;
sg_dma_len(&sg->sg) = PL011_DMA_BUFFER_SIZE;

@@ -386,12 +387,11 @@ static int pl011_sgbuf_init(struct dma_chan *chan, struct pl011_sgbuf *sg,
}

static void pl011_sgbuf_free(struct dma_chan *chan, struct pl011_sgbuf *sg,
- enum dma_data_direction dir)
+ enum dma_data_direction dir)
{
if (sg->buf) {
- dma_free_coherent(chan->device->dev,
- PL011_DMA_BUFFER_SIZE, sg->buf,
- sg_dma_address(&sg->sg));
+ dma_free_coherent(chan->device->dev, PL011_DMA_BUFFER_SIZE,
+ sg->buf, sg_dma_address(&sg->sg));
}
}

@@ -430,7 +430,7 @@ static void pl011_dma_probe(struct uart_amba_port *uap)
dma_cap_set(DMA_SLAVE, mask);

chan = dma_request_channel(mask, plat->dma_filter,
- plat->dma_tx_param);
+ plat->dma_tx_param);
if (!chan) {
dev_err(uap->port.dev, "no TX DMA channel!\n");
return;
@@ -471,12 +471,12 @@ static void pl011_dma_probe(struct uart_amba_port *uap)
* If the controller does, check for suitable residue processing
* otherwise assime all is well.
*/
- if (0 == dma_get_slave_caps(chan, &caps)) {
+ if (dma_get_slave_caps(chan, &caps) == 0) {
if (caps.residue_granularity ==
DMA_RESIDUE_GRANULARITY_DESCRIPTOR) {
dma_release_channel(chan);
dev_info(uap->port.dev,
- "RX DMA disabled - no residue processing\n");
+ "RX DMA disabled - no residue processing\n");
return;
}
}
@@ -505,18 +505,16 @@ static void pl011_dma_probe(struct uart_amba_port *uap)
else
uap->dmarx.poll_timeout = 3000;
} else if (!plat && dev->of_node) {
- uap->dmarx.auto_poll_rate = of_property_read_bool(
- dev->of_node, "auto-poll");
+ uap->dmarx.auto_poll_rate =
+ of_property_read_bool(dev->of_node, "auto-poll");
if (uap->dmarx.auto_poll_rate) {
u32 x;

- if (0 == of_property_read_u32(dev->of_node,
- "poll-rate-ms", &x))
+ if (of_property_read_u32(dev->of_node, "poll-rate-ms", &x) == 0)
uap->dmarx.poll_rate = x;
else
uap->dmarx.poll_rate = 100;
- if (0 == of_property_read_u32(dev->of_node,
- "poll-timeout-ms", &x))
+ if (of_property_read_u32(dev->of_node, "poll-timeout-ms", &x) == 0)
uap->dmarx.poll_timeout = x;
else
uap->dmarx.poll_timeout = 3000;
@@ -624,9 +622,9 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap)
if (count > PL011_DMA_BUFFER_SIZE)
count = PL011_DMA_BUFFER_SIZE;

- if (xmit->tail < xmit->head)
+ if (xmit->tail < xmit->head) {
memcpy(&dmatx->buf[0], &xmit->buf[xmit->tail], count);
- else {
+ } else {
size_t first = UART_XMIT_SIZE - xmit->tail;
size_t second;

@@ -648,7 +646,7 @@ static int pl011_dma_tx_refill(struct uart_amba_port *uap)
}

desc = dmaengine_prep_slave_sg(chan, &dmatx->sg, 1, DMA_MEM_TO_DEV,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc) {
dma_unmap_sg(dma_dev->dev, &dmatx->sg, 1, DMA_TO_DEVICE);
uap->dmatx.queued = false;
@@ -759,8 +757,9 @@ static inline bool pl011_dma_tx_start(struct uart_amba_port *uap)
if (pl011_dma_tx_refill(uap) > 0) {
uap->im &= ~UART011_TXIM;
pl011_write(uap->im, uap, REG_IMSC);
- } else
+ } else {
ret = false;
+ }
} else if (!(uap->dmacr & UART011_TXDMAE)) {
uap->dmacr |= UART011_TXDMAE;
pl011_write(uap->dmacr, uap, REG_DMACR);
@@ -836,9 +835,8 @@ static int pl011_dma_rx_trigger_dma(struct uart_amba_port *uap)
/* Start the RX DMA job */
sgbuf = uap->dmarx.use_buf_b ?
&uap->dmarx.sgbuf_b : &uap->dmarx.sgbuf_a;
- desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1,
- DMA_DEV_TO_MEM,
- DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+ desc = dmaengine_prep_slave_sg(rxchan, &sgbuf->sg, 1, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
/*
* If the DMA engine is busy and cannot prepare a
* channel, no big deal, the driver will fall back
@@ -894,14 +892,13 @@ static void pl011_dma_rx_chars(struct uart_amba_port *uap,

/* Pick the remain data from the DMA */
if (pending) {
-
/*
* First take all chars in the DMA pipe, then look in the FIFO.
* Note that tty_insert_flip_buf() tries to take as many chars
* as it can.
*/
dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken,
- pending);
+ pending);

uap->port.icount.rx += dma_count;
if (dma_count < pending)
@@ -983,8 +980,8 @@ static void pl011_dma_rx_irq(struct uart_amba_port *uap)
/* Switch buffer & re-trigger DMA job */
dmarx->use_buf_b = !dmarx->use_buf_b;
if (pl011_dma_rx_trigger_dma(uap)) {
- dev_dbg(uap->port.dev, "could not retrigger RX DMA job "
- "fall back to interrupt mode\n");
+ dev_dbg(uap->port.dev,
+ "could not retrigger RX DMA job fall back to interrupt mode\n");
uap->im |= UART011_RXIM;
pl011_write(uap->im, uap, REG_IMSC);
}
@@ -1031,8 +1028,8 @@ static void pl011_dma_rx_callback(void *data)
* get some IRQ immediately from RX.
*/
if (ret) {
- dev_dbg(uap->port.dev, "could not retrigger RX DMA job "
- "fall back to interrupt mode\n");
+ dev_dbg(uap->port.dev,
+ "could not retrigger RX DMA job fall back to interrupt mode\n");
uap->im |= UART011_RXIM;
pl011_write(uap->im, uap, REG_IMSC);
}
@@ -1077,7 +1074,7 @@ static void pl011_dma_rx_poll(struct timer_list *t)
dmataken = sgbuf->sg.length - dmarx->last_residue;
size = dmarx->last_residue - state.residue;
dma_count = tty_insert_flip_string(port, sgbuf->buf + dmataken,
- size);
+ size);
if (dma_count == size)
dmarx->last_residue = state.residue;
dmarx->last_jiffies = jiffies;
@@ -1090,7 +1087,6 @@ static void pl011_dma_rx_poll(struct timer_list *t)
*/
if (jiffies_to_msecs(jiffies - dmarx->last_jiffies)
> uap->dmarx.poll_timeout) {
-
spin_lock_irqsave(&uap->port.lock, flags);
pl011_dma_rx_stop(uap);
uap->im |= UART011_RXIM;
@@ -1102,7 +1098,7 @@ static void pl011_dma_rx_poll(struct timer_list *t)
del_timer(&uap->dmarx.timer);
} else {
mod_timer(&uap->dmarx.timer,
- jiffies + msecs_to_jiffies(uap->dmarx.poll_rate));
+ jiffies + msecs_to_jiffies(uap->dmarx.poll_rate));
}
}

@@ -1118,7 +1114,6 @@ static void pl011_dma_startup(struct uart_amba_port *uap)

uap->dmatx.buf = kmalloc(PL011_DMA_BUFFER_SIZE, GFP_KERNEL | __GFP_DMA);
if (!uap->dmatx.buf) {
- dev_err(uap->port.dev, "no memory for DMA TX buffer\n");
uap->port.fifosize = uap->fifosize;
return;
}
@@ -1169,13 +1164,12 @@ static void pl011_dma_startup(struct uart_amba_port *uap)

if (uap->using_rx_dma) {
if (pl011_dma_rx_trigger_dma(uap))
- dev_dbg(uap->port.dev, "could not trigger initial "
- "RX DMA job, fall back to interrupt mode\n");
+ dev_dbg(uap->port.dev,
+ "could not trigger initial RX DMA job, fall back to interrupt mode\n");
if (uap->dmarx.poll_rate) {
timer_setup(&uap->dmarx.timer, pl011_dma_rx_poll, 0);
mod_timer(&uap->dmarx.timer,
- jiffies +
- msecs_to_jiffies(uap->dmarx.poll_rate));
+ jiffies + msecs_to_jiffies(uap->dmarx.poll_rate));
uap->dmarx.last_residue = PL011_DMA_BUFFER_SIZE;
uap->dmarx.last_jiffies = jiffies;
}
@@ -1363,8 +1357,8 @@ static void pl011_stop_rx(struct uart_port *port)
struct uart_amba_port *uap =
container_of(port, struct uart_amba_port, port);

- uap->im &= ~(UART011_RXIM|UART011_RTIM|UART011_FEIM|
- UART011_PEIM|UART011_BEIM|UART011_OEIM);
+ uap->im &= ~(UART011_RXIM | UART011_RTIM | UART011_FEIM |
+ UART011_PEIM | UART011_BEIM | UART011_OEIM);
pl011_write(uap->im, uap, REG_IMSC);

pl011_dma_rx_stop(uap);
@@ -1384,7 +1378,7 @@ static void pl011_enable_ms(struct uart_port *port)
struct uart_amba_port *uap =
container_of(port, struct uart_amba_port, port);

- uap->im |= UART011_RIMIM|UART011_CTSMIM|UART011_DCDMIM|UART011_DSRMIM;
+ uap->im |= UART011_RIMIM | UART011_CTSMIM | UART011_DCDMIM | UART011_DSRMIM;
pl011_write(uap->im, uap, REG_IMSC);
}

@@ -1402,8 +1396,8 @@ __acquires(&uap->port.lock)
*/
if (pl011_dma_rx_available(uap)) {
if (pl011_dma_rx_trigger_dma(uap)) {
- dev_dbg(uap->port.dev, "could not trigger RX DMA job "
- "fall back to interrupt mode again\n");
+ dev_dbg(uap->port.dev,
+ "could not trigger RX DMA job fall back to interrupt mode again\n");
uap->im |= UART011_RXIM;
pl011_write(uap->im, uap, REG_IMSC);
} else {
@@ -1413,8 +1407,7 @@ __acquires(&uap->port.lock)
uap->dmarx.last_jiffies = jiffies;
uap->dmarx.last_residue = PL011_DMA_BUFFER_SIZE;
mod_timer(&uap->dmarx.timer,
- jiffies +
- msecs_to_jiffies(uap->dmarx.poll_rate));
+ jiffies + msecs_to_jiffies(uap->dmarx.poll_rate));
}
#endif
}
@@ -1561,18 +1554,17 @@ static irqreturn_t pl011_int(int irq, void *dev_id)
do {
check_apply_cts_event_workaround(uap);

- pl011_write(status & ~(UART011_TXIS|UART011_RTIS|
- UART011_RXIS),
+ pl011_write(status & ~(UART011_TXIS | UART011_RTIS | UART011_RXIS),
uap, REG_ICR);

- if (status & (UART011_RTIS|UART011_RXIS)) {
+ if (status & (UART011_RTIS | UART011_RXIS)) {
if (pl011_dma_rx_running(uap))
pl011_dma_rx_irq(uap);
else
pl011_rx_chars(uap);
}
- if (status & (UART011_DSRMIS|UART011_DCDMIS|
- UART011_CTSMIS|UART011_RIMIS))
+ if (status & (UART011_DSRMIS | UART011_DCDMIS |
+ UART011_CTSMIS | UART011_RIMIS))
pl011_modem_status(uap);
if (status & UART011_TXIS)
pl011_tx_chars(uap, true);
@@ -1712,7 +1704,7 @@ static int pl011_get_poll_char(struct uart_port *port)
}

static void pl011_put_poll_char(struct uart_port *port,
- unsigned char ch)
+ unsigned char ch)
{
struct uart_amba_port *uap =
container_of(port, struct uart_amba_port, port);
@@ -1914,13 +1906,13 @@ static int sbsa_uart_startup(struct uart_port *port)
}

static void pl011_shutdown_channel(struct uart_amba_port *uap,
- unsigned int lcrh)
+ unsigned int lcrh)
{
- unsigned long val;
+ unsigned long val;

- val = pl011_read(uap, lcrh);
- val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
- pl011_write(val, uap, lcrh);
+ val = pl011_read(uap, lcrh);
+ val &= ~(UART01x_LCRH_BRK | UART01x_LCRH_FEN);
+ pl011_write(val, uap, lcrh);
}

/*
@@ -2069,7 +2061,7 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
uap->dmarx.poll_rate = DIV_ROUND_UP(10000000, baud);
#endif

- if (baud > port->uartclk/16)
+ if (baud > port->uartclk / 16)
quot = DIV_ROUND_CLOSEST(port->uartclk * 8, baud);
else
quot = DIV_ROUND_CLOSEST(port->uartclk * 4, baud);
@@ -2151,9 +2143,9 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios,
* else we see data corruption.
*/
if (uap->vendor->oversampling) {
- if ((baud >= 3000000) && (baud < 3250000) && (quot > 1))
+ if (baud >= 3000000 && baud < 3250000 && quot > 1)
quot -= 1;
- else if ((baud > 3250000) && (quot > 2))
+ else if (baud > 3250000 && quot > 2)
quot -= 2;
}
/* Set baud rate */
@@ -2222,13 +2214,14 @@ static void pl011_config_port(struct uart_port *port, int flags)
static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser)
{
int ret = 0;
+
if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
ret = -EINVAL;
if (ser->irq < 0 || ser->irq >= nr_irqs)
ret = -EINVAL;
if (ser->baud_base < 9600)
ret = -EINVAL;
- if (port->mapbase != (unsigned long) ser->iomem_base)
+ if (port->mapbase != (unsigned long)ser->iomem_base)
ret = -EINVAL;
return ret;
}
@@ -2537,7 +2530,7 @@ static void qdf2400_e44_putc(struct uart_port *port, unsigned char c)
cpu_relax();
}

-static void qdf2400_e44_early_write(struct console *con, const char *s, unsigned n)
+static void qdf2400_e44_early_write(struct console *con, const char *s, unsigned int n)
{
struct earlycon_device *dev = con->data;

@@ -2556,7 +2549,7 @@ static void pl011_putc(struct uart_port *port, unsigned char c)
cpu_relax();
}

-static void pl011_early_write(struct console *con, const char *s, unsigned n)
+static void pl011_early_write(struct console *con, const char *s, unsigned int n)
{
struct earlycon_device *dev = con->data;

@@ -2617,6 +2610,7 @@ static int __init pl011_early_console_setup(struct earlycon_device *device,

return 0;
}
+
OF_EARLYCON_DECLARE(pl011, "arm,pl011", pl011_early_console_setup);
OF_EARLYCON_DECLARE(pl011, "arm,sbsa-uart", pl011_early_console_setup);

@@ -2640,6 +2634,7 @@ qdf2400_e44_early_console_setup(struct earlycon_device *device,
device->con->write = qdf2400_e44_early_write;
return 0;
}
+
EARLYCON_DECLARE(qdf2400_e44, qdf2400_e44_early_console_setup);

#else
@@ -2659,8 +2654,8 @@ static struct uart_driver amba_reg = {
static int pl011_probe_dt_alias(int index, struct device *dev)
{
struct device_node *np;
- static bool seen_dev_with_alias = false;
- static bool seen_dev_without_alias = false;
+ static bool seen_dev_with_alias;
+ static bool seen_dev_without_alias;
int ret = index;

if (!IS_ENABLED(CONFIG_OF))
@@ -2676,7 +2671,7 @@ static int pl011_probe_dt_alias(int index, struct device *dev)
ret = index;
} else {
seen_dev_with_alias = true;
- if (ret >= ARRAY_SIZE(amba_ports) || amba_ports[ret] != NULL) {
+ if (ret >= ARRAY_SIZE(amba_ports) || amba_ports[ret]) {
dev_warn(dev, "requested serial port %d not available.\n", ret);
ret = index;
}
@@ -2710,7 +2705,7 @@ static int pl011_find_free_port(void)
int i;

for (i = 0; i < ARRAY_SIZE(amba_ports); i++)
- if (amba_ports[i] == NULL)
+ if (!amba_ports[i])
return i;

return -EBUSY;
@@ -3002,7 +2997,7 @@ static struct amba_driver pl011_driver = {

static int __init pl011_init(void)
{
- printk(KERN_INFO "Serial: AMBA PL011 UART driver\n");
+ pr_info("Serial: AMBA PL011 UART driver\n");

if (platform_driver_register(&arm_sbsa_uart_platform_driver))
pr_warn("could not register SBSA UART platform driver\n");

--
2.42.0