[RFC PATCH v2 11/12] mtd: rawnand: ams-delta: Use GPIO API bitmap extension
From: jmkrzyszt@gmail.com (Janusz Krzysztofik)
Date: 2018-08-06 22:30:02
Also in:
linux-doc, linux-gpio, linux-omap, lkml
Subsystem:
memory technology devices (mtd), nand flash subsystem, the rest · Maintainers:
Miquel Raynal, Richard Weinberger, Vignesh Raghavendra, Linus Torvalds
Try to address the driver performance issues by replacing traditional get/set array function calls with their bitmap based equivalents. As long as fast bitmap processing path is not implemented in the new API extension, performance of the driver remains unchanged. Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> --- drivers/mtd/nand/raw/ams-delta.c | 19 +++---------------- 1 file changed, 3 insertions(+), 16 deletions(-)
diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c
index 30c461138195..7b08b2c441d3 100644
--- a/drivers/mtd/nand/raw/ams-delta.c
+++ b/drivers/mtd/nand/raw/ams-delta.c@@ -78,15 +78,9 @@ static void ams_delta_write_commit(struct ams_delta_nand *priv) static void ams_delta_write_next_byte(struct ams_delta_nand *priv, u_char byte) { - struct gpio_descs *data_gpiods = priv->data_gpiods; unsigned long bits = byte; - int i, value_array[data_gpiods->ndescs]; - - for (i = 0; i < data_gpiods->ndescs; i++) - value_array[i] = test_bit(i, &bits); - gpiod_set_raw_array_value(data_gpiods->ndescs, data_gpiods->desc, - value_array); + gpiod_set_raw_array_bitmap(priv->data_gpiods, &bits); ams_delta_write_commit(priv); }
@@ -106,22 +100,15 @@ static void ams_delta_write_first_byte(struct ams_delta_nand *priv, u_char byte) static u_char ams_delta_read_next_byte(struct ams_delta_nand *priv) { - struct gpio_descs *data_gpiods = priv->data_gpiods; - unsigned long bits = 0; - int i, value_array[data_gpiods->ndescs]; + unsigned long bits; gpiod_set_value(priv->gpiod_nre, 0); ndelay(40); - gpiod_get_raw_array_value(data_gpiods->ndescs, data_gpiods->desc, - value_array); + gpiod_get_raw_array_bitmap(priv->data_gpiods, &bits); gpiod_set_value(priv->gpiod_nre, 1); - for (i = 0; i < data_gpiods->ndescs; i++) - if (value_array[i]) - __set_bit(i, &bits); - return bits; }
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2.16.4