fsi: Aspeed: Add mutex to protect HW access

There is nothing to prevent multiple commands being executed
simultaneously. Add a mutex to prevent this.

Fixes: 606397d67f ("fsi: Add ast2600 master driver")
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Milton Miller <miltonm@us.ibm.com>
Signed-off-by: Eddie James <eajames@linux.ibm.com>
Signed-off-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/20201120004929.185239-1-joel@jms.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Eddie James 2020-11-20 11:19:29 +10:30 committed by Greg Kroah-Hartman
parent fe34761d9f
commit dfd7f2c1c5

View File

@ -8,6 +8,7 @@
#include <linux/io.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
@ -19,6 +20,7 @@
struct fsi_master_aspeed {
struct fsi_master master;
struct mutex lock; /* protect HW access */
struct device *dev;
void __iomem *base;
struct clk *clk;
@ -254,6 +256,8 @@ static int aspeed_master_read(struct fsi_master *master, int link,
addr |= id << 21;
addr += link * FSI_HUB_LINK_SIZE;
mutex_lock(&aspeed->lock);
switch (size) {
case 1:
ret = opb_readb(aspeed, fsi_base + addr, val);
@ -265,14 +269,14 @@ static int aspeed_master_read(struct fsi_master *master, int link,
ret = opb_readl(aspeed, fsi_base + addr, val);
break;
default:
return -EINVAL;
ret = -EINVAL;
goto done;
}
ret = check_errors(aspeed, ret);
if (ret)
return ret;
return 0;
done:
mutex_unlock(&aspeed->lock);
return ret;
}
static int aspeed_master_write(struct fsi_master *master, int link,
@ -287,6 +291,8 @@ static int aspeed_master_write(struct fsi_master *master, int link,
addr |= id << 21;
addr += link * FSI_HUB_LINK_SIZE;
mutex_lock(&aspeed->lock);
switch (size) {
case 1:
ret = opb_writeb(aspeed, fsi_base + addr, *(u8 *)val);
@ -298,14 +304,14 @@ static int aspeed_master_write(struct fsi_master *master, int link,
ret = opb_writel(aspeed, fsi_base + addr, *(__be32 *)val);
break;
default:
return -EINVAL;
ret = -EINVAL;
goto done;
}
ret = check_errors(aspeed, ret);
if (ret)
return ret;
return 0;
done:
mutex_unlock(&aspeed->lock);
return ret;
}
static int aspeed_master_link_enable(struct fsi_master *master, int link,
@ -320,17 +326,21 @@ static int aspeed_master_link_enable(struct fsi_master *master, int link,
reg = cpu_to_be32(0x80000000 >> bit);
if (!enable)
return opb_writel(aspeed, ctrl_base + FSI_MCENP0 + (4 * idx),
reg);
mutex_lock(&aspeed->lock);
if (!enable) {
ret = opb_writel(aspeed, ctrl_base + FSI_MCENP0 + (4 * idx), reg);
goto done;
}
ret = opb_writel(aspeed, ctrl_base + FSI_MSENP0 + (4 * idx), reg);
if (ret)
return ret;
goto done;
mdelay(FSI_LINK_ENABLE_SETUP_TIME);
return 0;
done:
mutex_unlock(&aspeed->lock);
return ret;
}
static int aspeed_master_term(struct fsi_master *master, int link, uint8_t id)
@ -431,9 +441,11 @@ static ssize_t cfam_reset_store(struct device *dev, struct device_attribute *att
{
struct fsi_master_aspeed *aspeed = dev_get_drvdata(dev);
mutex_lock(&aspeed->lock);
gpiod_set_value(aspeed->cfam_reset_gpio, 1);
usleep_range(900, 1000);
gpiod_set_value(aspeed->cfam_reset_gpio, 0);
mutex_unlock(&aspeed->lock);
return count;
}
@ -597,6 +609,7 @@ static int fsi_master_aspeed_probe(struct platform_device *pdev)
dev_set_drvdata(&pdev->dev, aspeed);
mutex_init(&aspeed->lock);
aspeed_master_init(aspeed);
rc = fsi_master_register(&aspeed->master);