gpiolib: Pass bitmaps, not integer arrays, to get/set array

Most users of get/set array functions iterate consecutive bits of data,
usually a single integer, while processing array of results obtained
from, or building an array of values to be passed to those functions.
Save time wasted on those iterations by changing the functions' API to
accept bitmaps.

All current users are updated as well.

More benefits from the change are expected as soon as planned support
for accepting/passing those bitmaps directly from/to respective GPIO
chip callbacks if applicable is implemented.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 20 insertions, 39 deletions

diff --git a/drivers/auxdisplay/hd44780.c b/drivers/auxdisplay/hd44780.c
index f1a42f0f1ded..e9a893384362 100644
--- a/drivers/auxdisplay/hd44780.c
+++ b/drivers/auxdisplay/hd44780.c
@@ -62,17 +62,12 @@ static void hd44780_strobe_gpio(struct hd44780 *hd)
 /* write to an LCD panel register in 8 bit GPIO mode */
 static void hd44780_write_gpio8(struct hd44780 *hd, u8 val, unsigned int rs)
 {
-	int values[10];	/* for DATA[0-7], RS, RW */
-	unsigned int i, n;
-
-	for (i = 0; i < 8; i++)
-		values[PIN_DATA0 + i] = !!(val & BIT(i));
-	values[PIN_CTRL_RS] = rs;
-	n = 9;
-	if (hd->pins[PIN_CTRL_RW]) {
-		values[PIN_CTRL_RW] = 0;
-		n++;
-	}
+	DECLARE_BITMAP(values, 10); /* for DATA[0-7], RS, RW */
+	unsigned int n;
+
+	values[0] = val;
+	__assign_bit(8, values, rs);
+	n = hd->pins[PIN_CTRL_RW] ? 10 : 9;
 
 	/* Present the data to the port */
 	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA0], values);
@@ -83,32 +78,25 @@ static void hd44780_write_gpio8(struct hd44780 *hd, u8 val, unsigned int rs)
 /* write to an LCD panel register in 4 bit GPIO mode */
 static void hd44780_write_gpio4(struct hd44780 *hd, u8 val, unsigned int rs)
 {
-	int values[10];	/* for DATA[0-7], RS, RW, but DATA[0-3] is unused */
-	unsigned int i, n;
+	DECLARE_BITMAP(values, 6); /* for DATA[4-7], RS, RW */
+	unsigned int n;
 
 	/* High nibble + RS, RW */
-	for (i = 4; i < 8; i++)
-		values[PIN_DATA0 + i] = !!(val & BIT(i));
-	values[PIN_CTRL_RS] = rs;
-	n = 5;
-	if (hd->pins[PIN_CTRL_RW]) {
-		values[PIN_CTRL_RW] = 0;
-		n++;
-	}
+	values[0] = val >> 4;
+	__assign_bit(4, values, rs);
+	n = hd->pins[PIN_CTRL_RW] ? 6 : 5;
 
 	/* Present the data to the port */
-	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
-				       &values[PIN_DATA4]);
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], values);
 
 	hd44780_strobe_gpio(hd);
 
 	/* Low nibble */
-	for (i = 0; i < 4; i++)
-		values[PIN_DATA4 + i] = !!(val & BIT(i));
+	values[0] &= ~0x0fUL;
+	values[0] |= val & 0x0f;
 
 	/* Present the data to the port */
-	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
-				       &values[PIN_DATA4]);
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], values);
 
 	hd44780_strobe_gpio(hd);
 }
@@ -155,23 +143,16 @@ static void hd44780_write_cmd_gpio4(struct charlcd *lcd, int cmd)
 /* Send 4-bits of a command to the LCD panel in raw 4 bit GPIO mode */
 static void hd44780_write_cmd_raw_gpio4(struct charlcd *lcd, int cmd)
 {
-	int values[10];	/* for DATA[0-7], RS, RW, but DATA[0-3] is unused */
+	DECLARE_BITMAP(values, 6); /* for DATA[4-7], RS, RW */
 	struct hd44780 *hd = lcd->drvdata;
-	unsigned int i, n;
+	unsigned int n;
 
 	/* Command nibble + RS, RW */
-	for (i = 0; i < 4; i++)
-		values[PIN_DATA4 + i] = !!(cmd & BIT(i));
-	values[PIN_CTRL_RS] = 0;
-	n = 5;
-	if (hd->pins[PIN_CTRL_RW]) {
-		values[PIN_CTRL_RW] = 0;
-		n++;
-	}
+	values[0] = cmd & 0x0f;
+	n = hd->pins[PIN_CTRL_RW] ? 6 : 5;
 
 	/* Present the data to the port */
-	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4],
-				       &values[PIN_DATA4]);
+	gpiod_set_array_value_cansleep(n, &hd->pins[PIN_DATA4], values);
 
 	hd44780_strobe_gpio(hd);
 }