From: Janusz Krzysztofik <jmkrzyszt@gmail.com>
To: Boris Brezillon <boris.brezillon@bootlin.com>,
Linus Walleij <linus.walleij@linaro.org>
Cc: Jonathan Corbet <corbet@lwn.net>,
Miquel Raynal <miquel.raynal@bootlin.com>,
Richard Weinberger <richard@nod.at>,
David Woodhouse <dwmw2@infradead.org>,
Brian Norris <computersforpeace@gmail.com>,
Marek Vasut <marek.vasut@gmail.com>,
Tony Lindgren <tony@atomide.com>,
Aaro Koskinen <aaro.koskinen@iki.fi>,
linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org,
linux-mtd@lists.infradead.org, linux-doc@vger.kernel.org,
linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org,
Janusz Krzysztofik <jmkrzyszt@gmail.com>
Subject: [RFC PATCH v2 09/12] gpiolib: Identify GPIO descriptor arrays with direct mapping
Date: Tue, 7 Aug 2018 00:29:15 +0200 [thread overview]
Message-ID: <20180806222918.12644-10-jmkrzyszt@gmail.com> (raw)
In-Reply-To: <20180806222918.12644-1-jmkrzyszt@gmail.com>
Certain GPIO array lookup results may map directly to GPIO pins of a
single GPIO chip in hardware order. If that condition is recognized
and handled efficiently, significant performance gain of get/set array
functions may be possible.
While processing a request for an array of GPIO descriptors, verify if
the descriptors just collected represent consecutive pins of a single
GPIO chip. Pass that information with the array to the caller so it
can benefit from enhanced performance as soon as bitmap based get/set
array functions which can make efficient use of that are available.
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
---
Documentation/driver-api/gpio/consumer.rst | 4 +++-
drivers/gpio/gpiolib.c | 14 ++++++++++++++
include/linux/gpio/consumer.h | 1 +
3 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/Documentation/driver-api/gpio/consumer.rst b/Documentation/driver-api/gpio/consumer.rst
index aa03f389d41d..38a990b5f3b6 100644
--- a/Documentation/driver-api/gpio/consumer.rst
+++ b/Documentation/driver-api/gpio/consumer.rst
@@ -109,11 +109,13 @@ For a function using multiple GPIOs all of those can be obtained with one call::
enum gpiod_flags flags)
This function returns a struct gpio_descs which contains an array of
-descriptors::
+descriptors. It may also contain a valid descriptor of a single GPIO chip in
+case the array strictly matches pin hardware layout of the chip::
struct gpio_descs {
unsigned int ndescs;
struct gpio_desc *desc[];
+ struct gpio_chip *chip;
}
The following function returns NULL instead of -ENOENT if no GPIOs have been
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index bdbfc95793e7..c50bcec6e2d7 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -4161,6 +4161,7 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
{
struct gpio_desc *desc;
struct gpio_descs *descs;
+ struct gpio_chip *chip;
int count;
count = gpiod_count(dev, con_id);
@@ -4177,6 +4178,19 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
gpiod_put_array(descs);
return ERR_CAST(desc);
}
+
+ /*
+ * Verify if the array qualifies for fast bitmap operations
+ * (single chip, pins in hardware order starting from 0)
+ * and mark the array with the chip descriptor if true.
+ */
+ chip = gpiod_to_chip(desc);
+ if (descs->chip == NULL)
+ descs->chip = chip;
+ if (!IS_ERR(descs->chip) && (chip != descs->chip ||
+ gpio_chip_hwgpio(desc) != descs->ndescs))
+ descs->chip = ERR_PTR(-EINVAL);
+
descs->desc[descs->ndescs] = desc;
descs->ndescs++;
}
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index 21ddbe440030..862ee027a02f 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -22,6 +22,7 @@ struct gpio_desc;
* gpiod_get_array().
*/
struct gpio_descs {
+ struct gpio_chip *chip;
unsigned int ndescs;
struct gpio_desc *desc[];
};
--
2.16.4
next prev parent reply other threads:[~2018-08-06 22:29 UTC|newest]
Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-07-18 23:57 [RFC PATCH 0/8] mtd: rawnand: ams-delta: Use gpio-omap accessors for data I/O Janusz Krzysztofik
2018-07-18 23:57 ` [RFC PATCH 1/8] mtd: rawnand: ams-delta: Use private structure Janusz Krzysztofik
2018-07-19 6:17 ` Boris Brezillon
2018-07-20 17:57 ` Janusz Krzysztofik
2018-07-18 23:57 ` [RFC PATCH 2/8] mtd: rawnand: ams-delta: Write protect device during probe Janusz Krzysztofik
2018-07-19 6:22 ` Boris Brezillon
2018-07-20 18:02 ` Janusz Krzysztofik
2018-07-18 23:57 ` [RFC PATCH 3/8] mtd: rawnand: ams-delta: Set port direction once per transfer Janusz Krzysztofik
2018-07-19 6:23 ` Boris Brezillon
2018-07-20 18:12 ` Janusz Krzysztofik
2018-07-20 19:29 ` Boris Brezillon
2018-07-18 23:57 ` [RFC PATCH 4/8] mtd: rawnand: ams-delta: Optimize pointer resolution on read/write Janusz Krzysztofik
2018-07-19 6:25 ` Boris Brezillon
2018-07-20 18:14 ` Janusz Krzysztofik
2018-07-20 19:29 ` Boris Brezillon
2018-07-18 23:57 ` [RFC PATCH 5/8] mtd: rawnand: ams-delta: Request data port GPIO resource Janusz Krzysztofik
2018-07-19 6:28 ` Boris Brezillon
2018-07-18 23:57 ` [RFC PATCH 6/8] gpio: omap: Add get/set_multiple() callbacks Janusz Krzysztofik
2018-07-29 20:29 ` Linus Walleij
2018-08-03 1:52 ` Grygorii Strashko
2018-08-03 16:47 ` Linus Walleij
2018-07-18 23:57 ` [RFC PATCH 7/8] mtd: rawnand: ams-delta: Check sanity of data GPIO resource Janusz Krzysztofik
2018-07-19 6:44 ` Boris Brezillon
2018-07-29 20:36 ` Linus Walleij
2018-07-29 21:16 ` Boris Brezillon
2018-07-29 20:33 ` Linus Walleij
2018-07-18 23:57 ` [RFC PATCH 8/8] mtd: rawnand: ams-delta: Use GPIO callbacks for data I/O Janusz Krzysztofik
2018-07-19 6:47 ` Boris Brezillon
2018-07-20 18:38 ` Janusz Krzysztofik
2018-07-20 19:48 ` Boris Brezillon
2018-07-19 6:15 ` [RFC PATCH 0/8] mtd: rawnand: ams-delta: Use gpio-omap accessors " Boris Brezillon
2018-07-20 17:55 ` Janusz Krzysztofik
2018-07-20 19:25 ` Boris Brezillon
2018-08-06 22:29 ` [RFC PATCH v2] mtd: rawnand: ams-delta: Use GPIO API " Janusz Krzysztofik
2018-08-06 22:29 ` [RFC PATCH v2 01/12] mtd: rawnand: ams-delta: Assign mtd->dev.parent, not mtd->owner Janusz Krzysztofik
2018-08-06 23:54 ` Marek Vasut
2018-08-07 21:55 ` Janusz Krzysztofik
2018-08-07 16:57 ` Boris Brezillon
2018-08-06 22:29 ` [RFC PATCH v2 02/12] mtd: rawnand: ams-delta: Use private structure Janusz Krzysztofik
2018-08-07 16:59 ` Boris Brezillon
2018-08-06 22:29 ` [RFC PATCH v2 03/12] ARM: OMAP1: ams-delta: Provide GPIO lookup table for NAND data port Janusz Krzysztofik
2018-08-07 16:59 ` Boris Brezillon
2018-08-10 10:10 ` Linus Walleij
2018-08-06 22:29 ` [RFC PATCH v2 04/12] mtd: rawnand: ams-delta: request data port GPIO resource Janusz Krzysztofik
2018-08-07 17:00 ` Boris Brezillon
2018-08-10 10:11 ` Linus Walleij
2018-08-06 22:29 ` [RFC PATCH v2 05/12] mtd: rawnand: ams-delta: use GPIO API for data read/write Janusz Krzysztofik
2018-08-06 23:57 ` Marek Vasut
2018-08-07 17:06 ` Boris Brezillon
2018-08-07 17:11 ` Janusz Krzysztofik
2018-08-10 10:25 ` Linus Walleij
2018-08-06 22:29 ` [RFC PATCH v2 06/12] ARM: OMAP1: ams-delta: drop obsolete NAND resources Janusz Krzysztofik
2018-08-06 22:29 ` [RFC PATCH v2 07/12] mtd: rawnand: ams-delta: Set port direction once per transfer Janusz Krzysztofik
2018-08-07 18:57 ` Boris Brezillon
2018-08-08 16:55 ` Janusz Krzysztofik
2018-08-08 17:42 ` Miquel Raynal
2018-08-06 22:29 ` [RFC PATCH v2 08/12] mtd: rawnand: ams-delta: Simplify pointer resolution on read/write Janusz Krzysztofik
2018-08-07 17:02 ` Boris Brezillon
2018-08-07 17:15 ` Janusz Krzysztofik
2018-08-06 22:29 ` Janusz Krzysztofik [this message]
2018-08-06 23:29 ` [RFC PATCH v2 09/12] gpiolib: Identify GPIO descriptor arrays with direct mapping Linus Walleij
2018-08-07 16:50 ` Janusz Krzysztofik
2018-08-07 17:10 ` Boris Brezillon
2018-08-07 17:14 ` Boris Brezillon
2018-08-07 17:19 ` Janusz Krzysztofik
2018-08-06 22:29 ` [RFC PATCH v2 10/12] gpiolib: Introduce bitmap get/set array API extension Janusz Krzysztofik
2018-08-06 22:29 ` [RFC PATCH v2 11/12] mtd: rawnand: ams-delta: Use GPIO API bitmap extension Janusz Krzysztofik
2018-08-06 22:29 ` [RFC PATCH v2 12/12] gpiolib: Add fast processing path to bitmap API functions Janusz Krzysztofik
2018-08-06 23:43 ` Linus Walleij
2018-08-07 17:29 ` Janusz Krzysztofik
2018-08-07 17:47 ` Boris Brezillon
2018-08-10 10:55 ` Linus Walleij
2018-08-13 22:34 ` [PATCH v3 0/7] mtd: rawnand: ams-delta: Use GPIO API for data I/O Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 1/7] mtd: rawnand: ams-delta: show parent device in sysfs Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 2/7] mtd: rawnand: ams-delta: Use private structure Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 3/7] ARM: OMAP1: ams-delta: Provide GPIO lookup table for NAND data port Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 4/7] mtd: rawnand: ams-delta: request data port GPIO resource Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 5/7] mtd: rawnand: ams-delta: Set port direction when needed Janusz Krzysztofik
2018-08-16 7:30 ` Boris Brezillon
2018-08-13 22:34 ` [PATCH v3 6/7] mtd: rawnand: ams-delta: Simplify pointer resolution on read/write Janusz Krzysztofik
2018-08-13 22:34 ` [PATCH v3 7/7] mtd: rawnand: ams-delta: use GPIO API for data I/O Janusz Krzysztofik
2018-08-16 7:39 ` Boris Brezillon
2018-11-21 11:08 ` Subject: [PATCH v4 0/4] mtd: rawnand: ams-delta: Use " Janusz Krzysztofik
2018-11-21 11:08 ` [PATCH v4 1/4] ARM: OMAP1: ams-delta: Provide GPIO lookup table for NAND data port Janusz Krzysztofik
2018-11-23 17:02 ` Tony Lindgren
2018-11-21 11:08 ` [PATCH v4 2/4] mtd: rawnand: ams-delta: Request data port GPIO resource Janusz Krzysztofik
2018-11-21 11:08 ` [PATCH v4 3/4] mtd: rawnand: ams-delta: Use GPIO API for data I/O Janusz Krzysztofik
2018-11-21 14:53 ` Boris Brezillon
2018-11-21 11:08 ` [PATCH v4 4/4] ARM: OMAP1: ams-delta: Drop obsolete NAND resources Janusz Krzysztofik
2018-11-21 14:56 ` Subject: [PATCH v4 0/4] mtd: rawnand: ams-delta: Use GPIO API for data I/O Boris Brezillon
2018-11-23 17:03 ` Tony Lindgren
2018-12-07 8:04 ` Miquel Raynal
2018-12-07 16:10 ` Tony Lindgren
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180806222918.12644-10-jmkrzyszt@gmail.com \
--to=jmkrzyszt@gmail.com \
--cc=aaro.koskinen@iki.fi \
--cc=boris.brezillon@bootlin.com \
--cc=computersforpeace@gmail.com \
--cc=corbet@lwn.net \
--cc=dwmw2@infradead.org \
--cc=linus.walleij@linaro.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-doc@vger.kernel.org \
--cc=linux-gpio@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mtd@lists.infradead.org \
--cc=linux-omap@vger.kernel.org \
--cc=marek.vasut@gmail.com \
--cc=miquel.raynal@bootlin.com \
--cc=richard@nod.at \
--cc=tony@atomide.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).