[PATCH 05/18] serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield

From: Hugo Villeneuve
Date: Tue Dec 19 2023 - 12:20:23 EST


From: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>

Replace the explicit sc16is7xx_lines bitfield declaration with the generic
macro DECLARE_BITMAP() to reserve just enough memory to contain all
required bits.

This also improves code self-documentation by showing the maximum number
of bits required.

This conversion now makes sc16is7xx_lines an array, so drop the "&" before
sc16is7xx_lines in all bit access functions.

Signed-off-by: Hugo Villeneuve <hvilleneuve@xxxxxxxxxxxx>
---
drivers/tty/serial/sc16is7xx.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/sc16is7xx.c b/drivers/tty/serial/sc16is7xx.c
index 8a038a9be09e..597280a5d0f3 100644
--- a/drivers/tty/serial/sc16is7xx.c
+++ b/drivers/tty/serial/sc16is7xx.c
@@ -346,7 +346,7 @@ struct sc16is7xx_port {
struct sc16is7xx_one p[];
};

-static unsigned long sc16is7xx_lines;
+static DECLARE_BITMAP(sc16is7xx_lines, SC16IS7XX_MAX_DEVS);

static struct uart_driver sc16is7xx_uart = {
.owner = THIS_MODULE,
@@ -1534,7 +1534,7 @@ static int sc16is7xx_probe(struct device *dev,
SC16IS7XX_IOCONTROL_SRESET_BIT);

for (i = 0; i < devtype->nr_uart; ++i) {
- s->p[i].port.line = find_first_zero_bit(&sc16is7xx_lines,
+ s->p[i].port.line = find_first_zero_bit(sc16is7xx_lines,
SC16IS7XX_MAX_DEVS);
if (s->p[i].port.line >= SC16IS7XX_MAX_DEVS) {
ret = -ERANGE;
@@ -1585,7 +1585,7 @@ static int sc16is7xx_probe(struct device *dev,
if (ret)
goto out_ports;

- set_bit(s->p[i].port.line, &sc16is7xx_lines);
+ set_bit(s->p[i].port.line, sc16is7xx_lines);

/* Enable EFR */
sc16is7xx_port_write(&s->p[i].port, SC16IS7XX_LCR_REG,
@@ -1644,7 +1644,7 @@ static int sc16is7xx_probe(struct device *dev,

out_ports:
for (i = 0; i < devtype->nr_uart; i++)
- if (test_and_clear_bit(s->p[i].port.line, &sc16is7xx_lines))
+ if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines))
uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port);

kthread_stop(s->kworker_task);
@@ -1672,7 +1672,7 @@ static void sc16is7xx_remove(struct device *dev)

for (i = 0; i < s->devtype->nr_uart; i++) {
kthread_cancel_delayed_work_sync(&s->p[i].ms_work);
- if (test_and_clear_bit(s->p[i].port.line, &sc16is7xx_lines))
+ if (test_and_clear_bit(s->p[i].port.line, sc16is7xx_lines))
uart_remove_one_port(&sc16is7xx_uart, &s->p[i].port);
sc16is7xx_power(&s->p[i].port, 0);
}
--
2.39.2