[char-misc-next 1/2] mei: fix read after read scenario

[char-misc-next 1/2] mei: fix read after read scenario

[Tomas Winkler]

mei read always has to be preceded by write but
'write write read read' scenario should work as well.
In this case the offset is not zero but new read should
be initiated

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
---
 drivers/misc/mei/main.c | 24 +++++++++++++-----------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index b9ad510..5e11b5b 100644
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -214,19 +214,21 @@ static ssize_t mei_read(struct file *file, char __user *ubuf,
 		goto out;
 	}
 
-	if (cl->read_cb && cl->read_cb->buf_idx > *offset) {
-		cb = cl->read_cb;
-		goto copy_buffer;
-	} else if (cl->read_cb && cl->read_cb->buf_idx > 0 &&
-		   cl->read_cb->buf_idx <= *offset) {
+	if (cl->read_cb) {
 		cb = cl->read_cb;
-		rets = 0;
-		goto free;
-	} else if ((!cl->read_cb || !cl->read_cb->buf_idx) && *offset > 0) {
-		/*Offset needs to be cleaned for contiguous reads*/
+		/* read what left */
+		if (cb->buf_idx > *offset)
+			goto copy_buffer;
+		/* offset is beyond buf_idx we have no more data return 0 */
+		if (cb->buf_idx > 0 && cb->buf_idx <= *offset) {
+			rets = 0;
+			goto free;
+		}
+		/* Offset needs to be cleaned for contiguous reads*/
+		if (cb->buf_idx == 0 && *offset > 0)
+			*offset = 0;
+	} else if (*offset > 0) {
 		*offset = 0;
-		rets = 0;
-		goto out;
 	}
 
 	err = mei_cl_read_start(cl, length);
-- 
1.8.1.2

[char-misc-next 2/2] mei: me: remove artificial singleton requirement

[Tomas Winkler]

There is only one device on the platform
drop mei_pdev and the mutex

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
---
 drivers/misc/mei/pci-me.c | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/drivers/misc/mei/pci-me.c b/drivers/misc/mei/pci-me.c
index a727464..a2f5520f 100644
--- a/drivers/misc/mei/pci-me.c
+++ b/drivers/misc/mei/pci-me.c
@@ -43,9 +43,6 @@
 #include "hw-me.h"
 #include "client.h"
 
-/* AMT device is a singleton on the platform */
-static struct pci_dev *mei_pdev;
-
 /* mei_pci_tbl - PCI Device ID Table */
 static DEFINE_PCI_DEVICE_TABLE(mei_me_pci_tbl) = {
 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, MEI_DEV_ID_82946GZ)},
@@ -88,8 +85,6 @@ static DEFINE_PCI_DEVICE_TABLE(mei_me_pci_tbl) = {
 
 MODULE_DEVICE_TABLE(pci, mei_me_pci_tbl);
 
-static DEFINE_MUTEX(mei_mutex);
-
 /**
  * mei_quirk_probe - probe for devices that doesn't valid ME interface
  *
@@ -126,17 +121,12 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	struct mei_me_hw *hw;
 	int err;
 
-	mutex_lock(&mei_mutex);
 
 	if (!mei_me_quirk_probe(pdev, ent)) {
 		err = -ENODEV;
 		goto end;
 	}
 
-	if (mei_pdev) {
-		err = -EEXIST;
-		goto end;
-	}
 	/* enable pci dev */
 	err = pci_enable_device(pdev);
 	if (err) {
@@ -195,13 +185,10 @@ static int mei_me_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (err)
 		goto release_irq;
 
-	mei_pdev = pdev;
 	pci_set_drvdata(pdev, dev);
 
 	schedule_delayed_work(&dev->timer_work, HZ);
 
-	mutex_unlock(&mei_mutex);
-
 	pr_debug("initialization successful.\n");
 
 	return 0;
@@ -220,7 +207,6 @@ release_regions:
 disable_device:
 	pci_disable_device(pdev);
 end:
-	mutex_unlock(&mei_mutex);
 	dev_err(&pdev->dev, "initialization failed.\n");
 	return err;
 }
@@ -238,9 +224,6 @@ static void mei_me_remove(struct pci_dev *pdev)
 	struct mei_device *dev;
 	struct mei_me_hw *hw;
 
-	if (mei_pdev != pdev)
-		return;
-
 	dev = pci_get_drvdata(pdev);
 	if (!dev)
 		return;
@@ -251,8 +234,6 @@ static void mei_me_remove(struct pci_dev *pdev)
 	dev_err(&pdev->dev, "stop\n");
 	mei_stop(dev);
 
-	mei_pdev = NULL;
-
 	/* disable interrupts */
 	mei_disable_interrupts(dev);
 
-- 
1.8.1.2