From: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Register the on-die spi device with the mtd subsystem.
Refcount spi object on _get and _put mtd callbacks.
CC: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
CC: Lucas De Marchi <lucas.demarchi@xxxxxxxxx>
Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
Signed-off-by: Alexander Usyskin <alexander.usyskin@xxxxxxxxx>
---
drivers/spi/spi-intel-dg.c | 111 +++++++++++++++++++++++++++++++++++++
1 file changed, 111 insertions(+)
diff --git a/drivers/spi/spi-intel-dg.c b/drivers/spi/spi-intel-dg.c
index 63c8292347e7..2ffc2d61fdc8 100644
--- a/drivers/spi/spi-intel-dg.c
+++ b/drivers/spi/spi-intel-dg.c
@@ -10,6 +10,8 @@
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/sizes.h>
@@ -17,6 +19,8 @@
struct intel_dg_spi {
struct kref refcnt;
+ struct mtd_info mtd;
+ struct mutex lock; /* region access lock */
void __iomem *base;
size_t size;
unsigned int nregions;
@@ -407,6 +411,23 @@ static int intel_dg_spi_init(struct intel_dg_spi *spi, struct device *device)
return n;
}
+static int intel_dg_spi_erase(struct mtd_info *mtd, struct erase_info *info)
+{
+ return 0;
+}
+
+static int intel_dg_spi_read(struct mtd_info *mtd, loff_t from, size_t len,
+ size_t *retlen, u_char *buf)
+{
+ return 0;
+}
+
+static int intel_dg_spi_write(struct mtd_info *mtd, loff_t to, size_t len,
+ size_t *retlen, const u_char *buf)
+{
+ return 0;
+}
+
static void intel_dg_spi_release(struct kref *kref)
{
struct intel_dg_spi *spi = container_of(kref, struct intel_dg_spi, refcnt);
@@ -415,9 +436,90 @@ static void intel_dg_spi_release(struct kref *kref)
pr_debug("freeing spi memory\n");
for (i = 0; i < spi->nregions; i++)
kfree(spi->regions[i].name);
+ mutex_destroy(&spi->lock);
kfree(spi);
}
+static int intel_dg_spi_get_device(struct mtd_info *mtd)
+{
+ struct mtd_info *master;
+ struct intel_dg_spi *spi;
+
+ if (!mtd)
+ return -ENODEV;
+
+ master = mtd_get_master(mtd);
+ spi = master->priv;
+ if (WARN_ON(!spi))
+ return -EINVAL;
+ pr_debug("get spi %s %d\n", mtd->name, kref_read(&spi->refcnt));
+ kref_get(&spi->refcnt);
+
+ return 0;
+}
+
+static void intel_dg_spi_put_device(struct mtd_info *mtd)
+{
+ struct mtd_info *master;
+ struct intel_dg_spi *spi;
+
+ if (!mtd)
+ return;
+
+ master = mtd_get_master(mtd);
+ spi = master->priv;
+ if (WARN_ON(!spi))
+ return;
+ pr_debug("put spi %s %d\n", mtd->name, kref_read(&spi->refcnt));
+ kref_put(&spi->refcnt, intel_dg_spi_release);
+}
+
+static int intel_dg_spi_init_mtd(struct intel_dg_spi *spi, struct device *device,
+ unsigned int nparts, bool writeable_override)
+{
+ unsigned int i;
+ unsigned int n;
+ struct mtd_partition *parts = NULL;
+ int ret;
+
+ dev_dbg(device, "registering with mtd\n");
+
+ spi->mtd.owner = THIS_MODULE;
+ spi->mtd.dev.parent = device;
+ spi->mtd.flags = MTD_CAP_NORFLASH | MTD_WRITEABLE;
+ spi->mtd.type = MTD_DATAFLASH;
+ spi->mtd.priv = spi;
+ spi->mtd._write = intel_dg_spi_write;
+ spi->mtd._read = intel_dg_spi_read;
+ spi->mtd._erase = intel_dg_spi_erase;
+ spi->mtd._get_device = intel_dg_spi_get_device;
+ spi->mtd._put_device = intel_dg_spi_put_device;
+ spi->mtd.writesize = SZ_1; /* 1 byte granularity */
+ spi->mtd.erasesize = SZ_4K; /* 4K bytes granularity */
+ spi->mtd.size = spi->size;
+
+ parts = kcalloc(spi->nregions, sizeof(*parts), GFP_KERNEL);
+ if (!parts)
+ return -ENOMEM;
+
+ for (i = 0, n = 0; i < spi->nregions && n < nparts; i++) {
+ if (!spi->regions[i].is_readable)
+ continue;
+ parts[n].name = spi->regions[i].name;
+ parts[n].offset = spi->regions[i].offset;
+ parts[n].size = spi->regions[i].size;
+ if (!spi->regions[i].is_writable && !writeable_override)
+ parts[n].mask_flags = MTD_WRITEABLE;
+ n++;
+ }
+
+ ret = mtd_device_register(&spi->mtd, parts, n);
+
+ kfree(parts);
+
+ return ret;
+}
+
static int intel_dg_spi_probe(struct auxiliary_device *aux_dev,
const struct auxiliary_device_id *aux_dev_id)
{
@@ -449,6 +551,7 @@ static int intel_dg_spi_probe(struct auxiliary_device *aux_dev,
if (!spi)
return -ENOMEM;
+ mutex_init(&spi->lock);
kref_init(&spi->refcnt);
spi->nregions = nregions;
@@ -481,6 +584,12 @@ static int intel_dg_spi_probe(struct auxiliary_device *aux_dev,
goto err;
}
+ ret = intel_dg_spi_init_mtd(spi, device, ret, ispi->writeable_override);
+ if (ret) {
+ dev_err(device, "failed init mtd %d\n", ret);
+ goto err;
+ }
+
dev_set_drvdata(&aux_dev->dev, spi);
return 0;
@@ -497,6 +606,8 @@ static void intel_dg_spi_remove(struct auxiliary_device *aux_dev)
if (!spi)
return;
+ mtd_device_unregister(&spi->mtd);
+
dev_set_drvdata(&aux_dev->dev, NULL);
kref_put(&spi->refcnt, intel_dg_spi_release);
--
2.34.1
