Patchwork [v6,01/35] mtd: st_spi_fsm: Allocate resources and register with MTD framework

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Submitter Lee Jones
Date March 11, 2014, 8:23 a.m.
Message ID <20140311082316.GJ2839@lee--X1>
Download mbox | patch
Permalink /patch/328986/
State Superseded
Headers show

Comments

Lee Jones - March 11, 2014, 8:23 a.m.
This is a new driver. It's used to communicate with a special type of
optimised Serial Flash Controller called the FSM. The FSM uses a subset
of the SPI protocol to communicate with supported NOR-Flash devices.

Acked-by Angus Clark <angus.clark@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---

Hi Brian,

Sorry about the previous fixup misses. There were a couple of patches
which I had failed to squash into the pack. Hopefully the rest of the
review will go more smoothly.

Kind regards,
Lee
 drivers/mtd/devices/Kconfig      |   8 +++
 drivers/mtd/devices/Makefile     |   1 +
 drivers/mtd/devices/st_spi_fsm.c | 107 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 116 insertions(+)
Brian Norris - March 20, 2014, 7:10 a.m.
Hi Lee,

I really can't take this patch separately. You'll need to resend the
whole series soon.

On Tue, Mar 11, 2014 at 08:23:16AM +0000, Lee Jones wrote:
> Sorry about the previous fixup misses. There were a couple of patches
> which I had failed to squash into the pack. Hopefully the rest of the
> review will go more smoothly.

Yeah... you missed a few more comments in the rest of the series too.
Can you please (for your own sake!) go through the rest of my comments
from before and see if you've missed any other important ones? I hate to
do the same work twice. The series mostly looks good, and I'd rather not
stall again for lack of attention to detail.

I'll comment on the couple of things I saw in just a bit.

Brian

Patch

diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig
index 0128138..1210bc2 100644
--- a/drivers/mtd/devices/Kconfig
+++ b/drivers/mtd/devices/Kconfig
@@ -210,6 +210,14 @@  config MTD_DOCG3
 	  M-Systems and now Sandisk. The support is very experimental,
 	  and doesn't give access to any write operations.
 
+config MTD_ST_SPI_FSM
+	tristate "ST Microelectronics SPI FSM Serial Flash Controller"
+	depends on ARM || SH
+	help
+	  This provides an MTD device driver for the ST Microelectronics
+	  SPI Fast Sequence Mode (FSM) Serial Flash Controller and support
+	  for a subset of connected Serial Flash devices.
+
 if MTD_DOCG3
 config BCH_CONST_M
 	default 14
diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile
index d83bd73..c68868f 100644
--- a/drivers/mtd/devices/Makefile
+++ b/drivers/mtd/devices/Makefile
@@ -16,6 +16,7 @@  obj-$(CONFIG_MTD_NAND_OMAP_BCH)	+= elm.o
 obj-$(CONFIG_MTD_SPEAR_SMI)	+= spear_smi.o
 obj-$(CONFIG_MTD_SST25L)	+= sst25l.o
 obj-$(CONFIG_MTD_BCM47XXSFLASH)	+= bcm47xxsflash.o
+obj-$(CONFIG_MTD_ST_SPI_FSM)    += st_spi_fsm.o
 
 
 CFLAGS_docg3.o			+= -I$(src)
diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
new file mode 100644
index 0000000..0de9648
--- /dev/null
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -0,0 +1,107 @@ 
+/*
+ * st_spi_fsm.c	- ST Fast Sequence Mode (FSM) Serial Flash Controller
+ *
+ * Author: Angus Clark <angus.clark@st.com>
+ *
+ * Copyright (C) 2010-2014 STicroelectronics Limited
+ *
+ * JEDEC probe based on drivers/mtd/devices/m25p80.c
+ *
+ * This code is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/mtd/mtd.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/of.h>
+
+struct stfsm {
+	struct device		*dev;
+	void __iomem		*base;
+	struct resource		*region;
+	struct mtd_info		mtd;
+	struct mutex		lock;
+};
+
+static int stfsm_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct resource *res;
+	struct stfsm *fsm;
+
+	if (!np) {
+		dev_err(&pdev->dev, "No DT found\n");
+		return -EINVAL;
+	}
+
+	fsm = devm_kzalloc(&pdev->dev, sizeof(*fsm), GFP_KERNEL);
+	if (!fsm)
+		return -ENOMEM;
+
+	fsm->dev = &pdev->dev;
+
+	platform_set_drvdata(pdev, fsm);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "Resource not found\n");
+		return -ENODEV;
+	}
+
+	fsm->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(fsm->base)) {
+		dev_err(&pdev->dev,
+			"Failed to reserve memory region [0x%08x-0x%08x]\n",
+			res->start, res->end);
+		return PTR_ERR(fsm->base);
+	}
+
+	mutex_init(&fsm->lock);
+
+	fsm->mtd.dev.parent	= &pdev->dev;
+	fsm->mtd.type		= MTD_NORFLASH;
+	fsm->mtd.writesize	= 4;
+	fsm->mtd.writebufsize	= fsm->mtd.writesize;
+	fsm->mtd.flags		= MTD_CAP_NORFLASH;
+
+	return mtd_device_parse_register(&fsm->mtd, NULL, NULL, NULL, 0);
+}
+
+static int stfsm_remove(struct platform_device *pdev)
+{
+	struct stfsm *fsm = platform_get_drvdata(pdev);
+	int err;
+
+	err = mtd_device_unregister(&fsm->mtd);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+static struct of_device_id stfsm_match[] = {
+	{ .compatible = "st,spi-fsm", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, stfsm_match);
+
+static struct platform_driver stfsm_driver = {
+	.probe		= stfsm_probe,
+	.remove		= stfsm_remove,
+	.driver		= {
+		.name	= "st-spi-fsm",
+		.owner	= THIS_MODULE,
+		.of_match_table = stfsm_match,
+	},
+};
+module_platform_driver(stfsm_driver);
+
+MODULE_AUTHOR("Angus Clark <angus.clark@st.com>");
+MODULE_DESCRIPTION("ST SPI FSM driver");
+MODULE_LICENSE("GPL");