From: s.hauer@pengutronix.de (Sascha Hauer)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v3 4/9] eeprom: Add a simple EEPROM framework for eeprom consumers
Date: Wed, 25 Mar 2015 08:16:30 +0100 [thread overview]
Message-ID: <20150325071630.GW9742@pengutronix.de> (raw)
In-Reply-To: <1427236219-18709-1-git-send-email-srinivas.kandagatla@linaro.org>
On Tue, Mar 24, 2015 at 10:30:19PM +0000, Srinivas Kandagatla wrote:
> This patch adds just consumers part of the framework just to enable easy
> review.
>
> Up until now, EEPROM drivers were stored in drivers/misc, where they all had to
> duplicate pretty much the same code to register a sysfs file, allow in-kernel
> users to access the content of the devices they were driving, etc.
>
> This was also a problem as far as other in-kernel users were involved, since
> the solutions used were pretty much different from on driver to another, there
> was a rather big abstraction leak.
>
> This introduction of this framework aims at solving this. It also introduces DT
> representation for consumer devices to go get the data they require (MAC
> Addresses, SoC/Revision ID, part numbers, and so on) from the EEPROMs.
>
> Having regmap interface to this framework would give much better
> abstraction for eeproms on different buses.
Thanks for working on this. This is something that is missing in the
kernel, it looks very promising to me.
Some comments inline
> +static struct eeprom_cell *__eeprom_cell_get(struct device_node *cell_np,
> + const char *ename,
> + struct eeprom_block *blocks,
> + int nblocks)
> +{
> + struct eeprom_cell *cell;
> + struct eeprom_device *eeprom = NULL;
No need to initialize.
> + struct property *prop;
> + const __be32 *vp;
> + u32 pv;
> + int i, rval;
> +
> + mutex_lock(&eeprom_mutex);
> +
> + eeprom = cell_np ? of_eeprom_find(cell_np->parent) : eeprom_find(ename);
> + if (!eeprom) {
> + mutex_unlock(&eeprom_mutex);
> + return ERR_PTR(-EPROBE_DEFER);
> + }
> +
> +/**
> + * of_eeprom_cell_get(): Get eeprom cell of device form a given index
> + *
> + * @dev: Device that will be interacted with
> + * @index: eeprom index in eeproms property.
> + *
> + * The return value will be an ERR_PTR() on error or a valid pointer
> + * to a struct eeprom_cell. The eeprom_cell will be freed by the
> + * eeprom_cell_put().
> + */
> +struct eeprom_cell *of_eeprom_cell_get(struct device *dev, int index)
> +{
I think the consumer API could be improved. The dev pointer is only used
to get the struct device_node out of it, so the device_node could be
passed in directly. As written in my other mail I think the binding
would be better like "calibration = <&tsens_calibration>;", so this
function could be:
of_eeprom_cell_get(struct device_node *np, const char *name)
With this we could also get eeprom cells from subnodes which do not have
a struct device bound to them.
> + struct device_node *cell_np;
> +
> + if (!dev || !dev->of_node)
> + return ERR_PTR(-EINVAL);
> +
> + cell_np = of_parse_phandle(dev->of_node, "eeproms", index);
> + if (!cell_np)
> + return ERR_PTR(-EPROBE_DEFER);
-EPROBE_DEFER is not appropriate here. If of_parse_phandle fails it
won't work next time.
> +
> + return __eeprom_cell_get(cell_np, NULL, NULL, 0);
> +}
> +EXPORT_SYMBOL_GPL(of_eeprom_cell_get);
> +
> +/**
> + * eeprom_cell_write(): Write to a given eeprom cell
> + *
> + * @cell: eeprom cell to be written.
> + * @buf: Buffer to be written.
> + * @len: length of buffer to be written to eeprom cell.
> + *
> + * The return value will be an non zero on error or a zero on successful write.
No, it returns the length.
> + */
> +int eeprom_cell_write(struct eeprom_cell *cell, const char *buf, ssize_t len)
> +{
> + struct eeprom_device *eeprom = cell->eeprom;
> + int i, rc, offset = 0;
> +
> + if (!eeprom || !eeprom->regmap || len != cell->size)
> + return -EINVAL;
> +
> + for (i = 0; i < cell->nblocks; i++) {
> + rc = regmap_bulk_write(eeprom->regmap, cell->blocks[i].offset,
> + buf + offset,
> + cell->blocks[i].count);
> +
> + if (IS_ERR_VALUE(rc))
> + return rc;
> +
> + offset += cell->blocks[i].count;
> + }
> +
> + return len;
> +}
> +EXPORT_SYMBOL_GPL(eeprom_cell_write);
> +
> +static inline char *eeprom_cell_read(struct eeprom_cell *cell, ssize_t *len)
> +{
> + return NULL;
> +}
The documentation above the real function states that this function
either returns an ERR_PTR() or a valid pointer. The wrapper should then
do the same.
Sascha
--
Pengutronix e.K. | |
Industrial Linux Solutions | http://www.pengutronix.de/ |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 |
Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
next prev parent reply other threads:[~2015-03-25 7:16 UTC|newest]
Thread overview: 153+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-19 17:07 [RFC PATCH 0/3] Add simple EEPROM Framework via regmap Srinivas Kandagatla
2015-02-19 17:08 ` [RFC PATCH 1/3] eeprom: Add a simple EEPROM framework Srinivas Kandagatla
2015-02-19 18:12 ` Andrew Lunn
2015-02-20 8:27 ` Srinivas Kandagatla
2015-02-20 2:36 ` Stephen Boyd
2015-02-20 8:14 ` Srinivas Kandagatla
2015-02-20 10:24 ` Srinivas Kandagatla
2015-02-20 17:21 ` Rob Herring
2015-02-20 19:25 ` Srinivas Kandagatla
2015-02-20 22:01 ` Rob Herring
2015-02-21 11:31 ` Srinivas Kandagatla
2015-02-22 14:34 ` Maxime Ripard
2015-02-22 14:32 ` Maxime Ripard
2015-02-23 0:57 ` Rob Herring
2015-02-23 23:11 ` Stephen Boyd
2015-02-24 7:08 ` Srinivas Kandagatla
2015-02-24 9:21 ` Maxime Ripard
2015-02-25 1:30 ` Stephen Boyd
2015-02-26 9:16 ` Srinivas Kandagatla
2015-02-26 13:21 ` Maxime Ripard
2015-02-26 14:56 ` Srinivas Kandagatla
2015-02-26 13:18 ` Maxime Ripard
2015-02-23 9:15 ` Sascha Hauer
2015-02-20 17:46 ` Russell King - ARM Linux
2015-02-20 19:00 ` Srinivas Kandagatla
2015-02-23 15:04 ` Mark Brown
2015-02-23 15:38 ` Srinivas Kandagatla
2015-02-19 17:08 ` [RFC PATCH 2/3] eeprom: sunxi: Move the SID driver to the eeprom framework Srinivas Kandagatla
2015-02-20 17:47 ` Russell King - ARM Linux
2015-02-19 17:08 ` [RFC PATCH 3/3] eeprom: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-02-20 17:48 ` Russell King - ARM Linux
2015-03-05 9:44 ` [PATCH v1 0/6] Add simple EEPROM Framework via regmap Srinivas Kandagatla
2015-03-05 9:45 ` [PATCH v1 1/6] eeprom: Add a simple EEPROM framework for eeprom providers Srinivas Kandagatla
2015-03-05 10:23 ` Paul Bolle
2015-03-05 10:35 ` Srinivas Kandagatla
2015-03-07 15:00 ` Mark Brown
2015-03-09 7:13 ` Srinivas Kandagatla
2015-03-05 9:45 ` [PATCH v1 2/6] eeprom: Add a simple EEPROM framework for eeprom consumers Srinivas Kandagatla
2015-03-05 9:46 ` [PATCH v1 3/6] eeprom: Add bindings for simple eeprom framework Srinivas Kandagatla
2015-03-05 20:11 ` Rob Herring
2015-03-05 22:34 ` Srinivas Kandagatla
2015-03-05 9:46 ` [PATCH v1 4/6] eeprom: sunxi: Move the SID driver to the " Srinivas Kandagatla
2015-03-05 10:15 ` Paul Bolle
2015-03-05 18:36 ` Maxime Ripard
2015-03-05 9:46 ` [PATCH v1 5/6] eeprom: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-03-05 10:02 ` Paul Bolle
2015-03-05 10:10 ` Srinivas Kandagatla
2015-03-05 9:46 ` [PATCH v1 6/6] eeprom: Add to MAINTAINERS for eeprom framework Srinivas Kandagatla
2015-03-13 9:49 ` [PATCH v2 0/7] Add simple EEPROM Framework via regmap Srinivas Kandagatla
2015-03-13 9:50 ` [PATCH v2 1/7] eeprom: Add a simple EEPROM framework for eeprom providers Srinivas Kandagatla
2015-03-23 21:09 ` Mark Brown
2015-03-23 22:05 ` Srinivas Kandagatla
2015-03-24 9:18 ` Srinivas Kandagatla
2015-03-24 17:23 ` Mark Brown
2015-03-24 18:34 ` Srinivas Kandagatla
2015-03-24 19:02 ` Mark Brown
2015-03-24 19:26 ` Srinivas Kandagatla
2015-03-24 20:55 ` Mark Brown
2015-03-13 9:50 ` [PATCH v2 2/7] eeprom: Add a simple EEPROM framework for eeprom consumers Srinivas Kandagatla
2015-03-13 9:50 ` [PATCH v2 3/7] eeprom: Add bindings for simple eeprom framework Srinivas Kandagatla
2015-03-13 9:50 ` [PATCH v2 4/7] eeprom: sunxi: Move the SID driver to the " Srinivas Kandagatla
2015-03-13 9:50 ` [PATCH v2 5/7] eeprom: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-03-13 9:50 ` [PATCH v2 6/7] eeprom: qfprom: Add bindings for qfprom Srinivas Kandagatla
2015-03-13 9:51 ` [PATCH v2 7/7] eeprom: Add to MAINTAINERS for eeprom framework Srinivas Kandagatla
2015-03-24 22:28 ` [PATCH v3 0/9] Add simple EEPROM Framework via regmap Srinivas Kandagatla
2015-03-24 22:29 ` [PATCH v3 1/9] regmap: Introduce regmap_get_max_register Srinivas Kandagatla
2015-03-24 22:36 ` Mark Brown
2015-03-24 23:05 ` Srinivas Kandagatla
2015-03-24 23:23 ` Joe Perches
2015-03-24 22:30 ` [PATCH v3 2/9] regmap: Introduce regmap_get_reg_stride Srinivas Kandagatla
2015-03-24 22:37 ` Mark Brown
2015-03-24 23:07 ` Srinivas Kandagatla
2015-03-24 22:30 ` [PATCH v3 3/9] eeprom: Add a simple EEPROM framework for eeprom providers Srinivas Kandagatla
2015-03-24 22:53 ` Mark Brown
2015-03-26 16:23 ` Srinivas Kandagatla
2015-03-24 22:30 ` [PATCH v3 4/9] eeprom: Add a simple EEPROM framework for eeprom consumers Srinivas Kandagatla
2015-03-25 7:16 ` Sascha Hauer [this message]
2015-03-25 12:29 ` Srinivas Kandagatla
2015-03-24 22:30 ` [PATCH v3 5/9] eeprom: Add bindings for simple eeprom framework Srinivas Kandagatla
2015-03-25 7:10 ` Sascha Hauer
2015-03-25 16:40 ` Maxime Ripard
2015-03-24 22:30 ` [PATCH v3 6/9] eeprom: sunxi: Move the SID driver to the " Srinivas Kandagatla
2015-03-24 22:30 ` [PATCH v3 7/9] eeprom: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-03-24 22:31 ` [PATCH v3 8/9] eeprom: qfprom: Add bindings for qfprom Srinivas Kandagatla
2015-03-25 0:28 ` Bjorn Andersson
2015-03-24 22:31 ` [PATCH v3 9/9] eeprom: Add to MAINTAINERS for eeprom framework Srinivas Kandagatla
2015-03-30 21:54 ` [PATCH v4 00/10] Add simple EEPROM Framework via regmap Srinivas Kandagatla
2015-03-30 21:56 ` [PATCH v4 01/10] regmap: Introduce regmap_get_max_register Srinivas Kandagatla
2015-05-04 12:05 ` Mark Brown
2015-03-30 21:57 ` [PATCH v4 02/10] regmap: Introduce regmap_get_reg_stride Srinivas Kandagatla
2015-03-30 21:57 ` [PATCH v4 03/10] eeprom: Add a simple EEPROM framework for eeprom providers Srinivas Kandagatla
2015-03-30 21:57 ` [PATCH v4 04/10] eeprom: Add a simple EEPROM framework for eeprom consumers Srinivas Kandagatla
2015-04-07 18:45 ` Stephen Boyd
2015-04-07 20:09 ` Srinivas Kandagatla
2015-04-09 14:45 ` Stephen Boyd
2015-04-10 11:45 ` Maxime Ripard
2015-05-05 11:46 ` Srinivas Kandagatla
2015-05-08 5:23 ` Sascha Hauer
2015-05-06 17:28 ` Mark Brown
2015-03-30 21:57 ` [PATCH v4 05/10] eeprom: Add bindings for simple eeprom framework Srinivas Kandagatla
2015-04-06 13:32 ` Matt Porter
2015-04-06 14:11 ` Rob Herring
2015-04-06 15:04 ` Matt Porter
2015-04-07 17:35 ` Srinivas Kandagatla
2015-04-07 17:46 ` Mark Brown
2015-04-07 18:03 ` Srinivas Kandagatla
2015-04-07 19:46 ` Matt Porter
2015-04-08 9:24 ` Srinivas Kandagatla
2015-03-30 21:58 ` [PATCH v4 06/10] eeprom: Add simple eeprom-mmio consumer helper functions Srinivas Kandagatla
2015-03-30 21:58 ` [PATCH v4 07/10] eeprom: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-03-30 21:58 ` [PATCH v4 08/10] eeprom: qfprom: Add bindings for qfprom Srinivas Kandagatla
2015-03-30 21:58 ` [PATCH v4 09/10] eeprom: sunxi: Move the SID driver to the eeprom framework Srinivas Kandagatla
2015-03-30 21:58 ` [PATCH v4 10/10] eeprom: Add to MAINTAINERS for " Srinivas Kandagatla
2015-05-21 16:42 ` [PATCH v5 00/11] Add simple NVMEM Framework via regmap Srinivas Kandagatla
2015-05-21 16:42 ` [PATCH v5 01/11] regmap: Introduce regmap_get_max_register Srinivas Kandagatla
2015-05-22 11:18 ` Mark Brown
2015-05-21 16:42 ` [PATCH v5 02/11] regmap: Introduce regmap_get_reg_stride Srinivas Kandagatla
2015-05-22 11:19 ` Mark Brown
2015-05-21 16:43 ` [PATCH v5 03/11] nvmem: Add a simple NVMEM framework for nvmem providers Srinivas Kandagatla
2015-06-16 22:43 ` Stephen Boyd
2015-06-18 12:46 ` Srinivas Kandagatla
2015-06-24 0:24 ` Stephen Boyd
2015-06-24 10:05 ` Srinivas Kandagatla
2015-05-21 16:43 ` [PATCH v5 04/11] nvmem: Add a simple NVMEM framework for consumers Srinivas Kandagatla
2015-06-16 22:29 ` Stephen Boyd
2015-06-17 8:00 ` Sascha Hauer
2015-06-18 12:56 ` Srinivas Kandagatla
2015-05-21 16:43 ` [PATCH v5 05/11] nvmem: Add nvmem_device based consumer apis Srinivas Kandagatla
2015-06-16 22:49 ` Stephen Boyd
2015-06-18 12:57 ` Srinivas Kandagatla
2015-05-21 16:44 ` [PATCH v5 06/11] nvmem: Add bindings for simple nvmem framework Srinivas Kandagatla
2015-06-16 22:53 ` Stephen Boyd
2015-06-18 13:01 ` Srinivas Kandagatla
2015-06-19 10:36 ` maitysanchayan at gmail.com
2015-06-19 10:59 ` Srinivas Kandagatla
2015-05-21 16:44 ` [PATCH v5 07/11] nvmem: Add simple nvmem-mmio consumer helper functions Srinivas Kandagatla
2015-06-16 22:58 ` Stephen Boyd
2015-06-18 13:08 ` Srinivas Kandagatla
2015-05-21 16:44 ` [PATCH v5 08/11] nvmem: qfprom: Add Qualcomm QFPROM support Srinivas Kandagatla
2015-06-16 23:00 ` Stephen Boyd
2015-06-18 13:22 ` Srinivas Kandagatla
2015-05-21 16:44 ` [PATCH v5 09/11] nvmem: qfprom: Add bindings for qfprom Srinivas Kandagatla
2015-06-16 23:01 ` Stephen Boyd
2015-05-21 16:45 ` [PATCH v5 11/11] nvmem: Add to MAINTAINERS for nvmem framework Srinivas Kandagatla
2015-05-21 16:45 ` [PATCH v5 10/11] nvmem: sunxi: Move the SID driver to the " Srinivas Kandagatla
2015-06-16 23:04 ` Stephen Boyd
2015-06-18 13:09 ` Srinivas Kandagatla
2015-05-25 16:51 ` [PATCH v5 00/11] Add simple NVMEM Framework via regmap Pantelis Antoniou
2015-05-26 9:12 ` Srinivas Kandagatla
2015-05-26 17:54 ` Pantelis Antoniou
2015-05-29 1:20 ` Dan Williams
2015-05-29 7:09 ` Srinivas Kandagatla
2015-05-29 21:44 ` Dan Williams
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=20150325071630.GW9742@pengutronix.de \
--to=s.hauer@pengutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
/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).