[PATCH 8/9] staging: dgap: cleanup dgap_firmware_load() function

[PATCH 8/9] staging: dgap: cleanup dgap_firmware_load() function

[Daeseok Youn]

The dgap_firmware_load() has a lot of stuff beside
loding firmware. So some registering and initializing
for device are moved into dgap_init_one().

And also adds unwinding on error in dgap_init_one().

Signed-off-by: Daeseok Youn <daeseok.youn@gmail.com>
---
 drivers/staging/dgap/dgap.c |   81 ++++++++++++++++++++++++++----------------
 1 files changed, 50 insertions(+), 31 deletions(-)

diff --git a/drivers/staging/dgap/dgap.c b/drivers/staging/dgap/dgap.c
index c0016bd..e1347fb 100644
--- a/drivers/staging/dgap/dgap.c
+++ b/drivers/staging/dgap/dgap.c
@@ -199,7 +199,8 @@ static void dgap_do_reset_board(struct board_t *brd);
 static int dgap_test_bios(struct board_t *brd);
 static int dgap_test_fep(struct board_t *brd);
 static int dgap_tty_register_ports(struct board_t *brd);
-static int dgap_firmware_load(struct pci_dev *pdev, int card_type);
+static int dgap_firmware_load(struct pci_dev *pdev, int card_type,
+			      struct board_t* brd);
 
 static void dgap_cleanup_module(void);
 
@@ -571,6 +572,7 @@ static int dgap_init_pci(void)
 static int dgap_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
 	int rc;
+	struct board_t* brd;
 
 	if (dgap_numboards >= MAXBOARDS)
 		return -EPERM;
@@ -583,8 +585,51 @@ static int dgap_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (rc)
 		return rc;
 
-	dgap_numboards++;
-	return dgap_firmware_load(pdev, ent->driver_data);
+	brd = dgap_board[dgap_numboards++];
+	rc = dgap_firmware_load(pdev, ent->driver_data, brd);
+	if (rc)
+		goto free_brd;
+
+	rc = dgap_alloc_flipbuf(brd);
+	if (rc)
+		goto free_brd;
+
+	rc = dgap_tty_register(brd);
+	if (rc)
+		goto free_flipbuf;
+
+	rc = dgap_request_irq(brd);
+	if (rc)
+		goto unregister_tty;
+
+	/*
+	 * Do tty device initialization.
+	 */
+	rc = dgap_tty_init(brd);
+	if (rc < 0)
+		goto free_irq;
+
+	rc = dgap_tty_register_ports(brd);
+	if (rc)
+		goto tty_free;
+
+	brd->state = BOARD_READY;
+	brd->dpastatus = BD_RUNNING;
+
+	return 0;
+
+tty_free:
+	dgap_tty_free(brd);
+free_irq:
+	dgap_free_irq(brd);
+unregister_tty:
+	dgap_tty_unregister(brd);
+free_flipbuf:
+	dgap_free_flipbuf(brd);
+free_brd:
+	kfree(brd);
+	dgap_board[--dgap_numboards] = NULL;
+	return rc;
 }
 
 static void dgap_remove_one(struct pci_dev *dev)
@@ -824,9 +869,9 @@ static void dgap_free_irq(struct board_t *brd)
 		free_irq(brd->irq, brd);
 }
 
-static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
+static int dgap_firmware_load(struct pci_dev *pdev, int card_type,
+			      struct board_t* brd)
 {
-	struct board_t *brd = dgap_board[dgap_numboards - 1];
 	const struct firmware *fw;
 	char *tmp_ptr;
 	int ret;
@@ -867,9 +912,6 @@ static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
 		kfree(dgap_config_buf);
 	}
 
-	ret = dgap_alloc_flipbuf(brd);
-	if (ret)
-		return ret;
 	/*
 	 * Match this board to a config the user created for us.
 	 */
@@ -891,14 +933,6 @@ static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
 		return -EINVAL;
 	}
 
-	ret = dgap_tty_register(brd);
-	if (ret)
-		return ret;
-
-	ret = dgap_request_irq(brd);
-	if (ret)
-		return ret;
-
 	if (fw_info[card_type].bios_name) {
 		ret = request_firmware(&fw, fw_info[card_type].bios_name,
 					&pdev->dev);
@@ -961,21 +995,6 @@ static int dgap_firmware_load(struct pci_dev *pdev, int card_type)
 		release_firmware(fw);
 	}
 #endif
-	/*
-	 * Do tty device initialization.
-	 */
-	ret = dgap_tty_init(brd);
-	if (ret < 0)
-		return ret;
-
-	ret = dgap_tty_register_ports(brd);
-	if (ret) {
-		dgap_tty_free(brd);
-		return ret;
-	}
-
-	brd->state = BOARD_READY;
-	brd->dpastatus = BD_RUNNING;
 
 	return 0;
 }
-- 
1.7.1

Re: [PATCH 8/9] staging: dgap: cleanup dgap_firmware_load() function

[Dan Carpenter]

On Fri, Jun 13, 2014 at 04:43:37PM +0900, Daeseok Youn wrote:
> @@ -583,8 +585,51 @@ static int dgap_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
>  	if (rc)
>  		return rc;
>  
> -	dgap_numboards++;
> -	return dgap_firmware_load(pdev, ent->driver_data);
> +	brd = dgap_board[dgap_numboards++];

I don't like the way the current code uses dgap_numboards and hiding
the ++ in here makes it even worse.

My thinking is that dgap_found_board() shouldn't touch dgap_board[] but
instead of instead it should return a pointer to "brd".  Then the code
in dgap_init_one() does:

	brd = dgap_found_board();
	if (!brd)
		return -ENODEV;

	/* code until the end of the function */

	dgap_board[dgap_numboards++] = brd;
	return 0;

tty_free:
	/* error path */

This could be done in a follow on patch.

TODO-list: 2014-06-13: dgap: make dgap_found_board() return a brd pointer.

> +	rc = dgap_firmware_load(pdev, ent->driver_data, brd);
> +	if (rc)
> +		goto free_brd;
> +
> +	rc = dgap_alloc_flipbuf(brd);
> +	if (rc)
> +		goto free_brd;
> +
> +	rc = dgap_tty_register(brd);
> +	if (rc)
> +		goto free_flipbuf;
> +
> +	rc = dgap_request_irq(brd);
> +	if (rc)
> +		goto unregister_tty;
> +
> +	/*
> +	 * Do tty device initialization.
> +	 */
> +	rc = dgap_tty_init(brd);
> +	if (rc < 0)
> +		goto free_irq;
> +
> +	rc = dgap_tty_register_ports(brd);
> +	if (rc)
> +		goto tty_free;
> +
> +	brd->state = BOARD_READY;
> +	brd->dpastatus = BD_RUNNING;
> +
> +	return 0;
> +
> +tty_free:
> +	dgap_tty_free(brd);
> +free_irq:
> +	dgap_free_irq(brd);
> +unregister_tty:
> +	dgap_tty_unregister(brd);
> +free_flipbuf:
> +	dgap_free_flipbuf(brd);
> +free_brd:
> +	kfree(brd);

This isn't complete.  We need a dgap_unfound_board() which frees brd
and calls the inverse of dgap_do_remap().  Obviously "found" and
"unfound" are not the smartest names in the universe.

That said, I'm inclined to say that we can fix this up in a later patch.
This patch is clearly an improvement on the existing code and I'm not
sure it's possible to fix *everything* in one go.

TODO-list:  2014-06-13: dgap: call dgap_unfound_board() on error in dgap_init_one()

> +	dgap_board[--dgap_numboards] = NULL;
> +	return rc;
>  }

regards,
dan carpenter