[PATCH] staging: gpib: Add return value to request_control

From: Dave Penkler
Date: Sat Feb 22 2025 - 15:23:19 EST

A number of drivers are unable to release control due to
hardware or software limitations. As request_control was defined
as void - no error could be signalled. Some drivers also did
not implement request_control correctly by setting
controller_in_charge instead of system_controller.

This patch changes the prototype of request_control to int
and adds the appropriate checking and returns. In the case
that a board cannot release control EPERM is returned. The
faulty implementations have been corrected.

Signed-off-by: Dave Penkler <dpenkler@xxxxxxxxx>
---
.../gpib/agilent_82350b/agilent_82350b.c | 7 +++--
.../gpib/agilent_82357a/agilent_82357a.c | 31 +++++++++----------
drivers/staging/gpib/cb7210/cb7210.c | 4 +--
drivers/staging/gpib/cec/cec_gpib.c | 4 +--
drivers/staging/gpib/common/gpib_os.c | 4 +--
drivers/staging/gpib/common/iblib.c | 15 ++++++---
drivers/staging/gpib/eastwood/fluke_gpib.c | 4 +--
drivers/staging/gpib/fmh_gpib/fmh_gpib.c | 4 +--
drivers/staging/gpib/gpio/gpib_bitbang.c | 21 ++++++++-----
drivers/staging/gpib/hp_82335/hp82335.c | 4 +--
drivers/staging/gpib/hp_82341/hp_82341.c | 4 +--
drivers/staging/gpib/include/gpib_proto.h | 2 +-
drivers/staging/gpib/include/gpib_types.h | 2 +-
drivers/staging/gpib/include/nec7210.h | 4 +--
drivers/staging/gpib/include/tms9914.h | 4 +--
drivers/staging/gpib/ines/ines.h | 2 +-
drivers/staging/gpib/ines/ines_gpib.c | 4 +--
.../gpib/lpvo_usb_gpib/lpvo_usb_gpib.c | 14 +++++----
drivers/staging/gpib/nec7210/nec7210.c | 5 +--
drivers/staging/gpib/ni_usb/ni_usb_gpib.c | 8 ++---
drivers/staging/gpib/pc2/pc2_gpib.c | 4 +--
drivers/staging/gpib/tms9914/tms9914.c | 6 ++--
drivers/staging/gpib/tnt4882/tnt4882_gpib.c | 6 ++--
23 files changed, 91 insertions(+), 72 deletions(-)

diff --git a/drivers/staging/gpib/agilent_82350b/agilent_82350b.c b/drivers/staging/gpib/agilent_82350b/agilent_82350b.c
index f83e1f321561..ba75cf6e0de0 100644
--- a/drivers/staging/gpib/agilent_82350b/agilent_82350b.c
+++ b/drivers/staging/gpib/agilent_82350b/agilent_82350b.c
@@ -339,10 +339,11 @@ static int agilent_82350b_go_to_standby(gpib_board_t *board)
return tms9914_go_to_standby(board, &priv->tms9914_priv);
}

-static void agilent_82350b_request_system_control(gpib_board_t *board, int request_control)
+static int agilent_82350b_request_system_control(gpib_board_t *board, int request_control)

{
struct agilent_82350b_priv *a_priv = board->private_data;
+ int retval;

if (request_control) {
a_priv->card_mode_bits |= CM_SYSTEM_CONTROLLER_BIT;
@@ -354,7 +355,9 @@ static void agilent_82350b_request_system_control(gpib_board_t *board, int reque
writeb(0, a_priv->gpib_base + INTERNAL_CONFIG_REG);
}
writeb(a_priv->card_mode_bits, a_priv->gpib_base + CARD_MODE_REG);
- tms9914_request_system_control(board, &a_priv->tms9914_priv, request_control);
+ retval = tms9914_request_system_control(board, &a_priv->tms9914_priv, request_control);
+
+ return retval;
}

static void agilent_82350b_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/agilent_82357a/agilent_82357a.c b/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
index e0d36f0dff25..76573aee4a4f 100644
--- a/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
+++ b/drivers/staging/gpib/agilent_82357a/agilent_82357a.c
@@ -751,8 +751,7 @@ static int agilent_82357a_go_to_standby(gpib_board_t *board)
return 0;
}

-//FIXME should change prototype to return int
-static void agilent_82357a_request_system_control(gpib_board_t *board, int request_control)
+static int agilent_82357a_request_system_control(gpib_board_t *board, int request_control)
{
struct agilent_82357a_priv *a_priv = board->private_data;
struct usb_device *usb_dev;
@@ -761,19 +760,15 @@ static void agilent_82357a_request_system_control(gpib_board_t *board, int reque
int i = 0;

if (!a_priv->bus_interface)
- return; // -ENODEV;
+ return -ENODEV;

+ if (!request_control)
+ return -EPERM; /* can't not be system controller */
usb_dev = interface_to_usbdev(a_priv->bus_interface);
/* 82357B needs bit to be set in 9914 AUXCR register */
writes[i].address = AUXCR;
- if (request_control) {
- writes[i].value = AUX_RQC;
- a_priv->hw_control_bits |= SYSTEM_CONTROLLER;
- } else {
- writes[i].value = AUX_RLC;
- a_priv->is_cic = 0;
- a_priv->hw_control_bits &= ~SYSTEM_CONTROLLER;
- }
+ writes[i].value = AUX_RQC;
+ a_priv->hw_control_bits |= SYSTEM_CONTROLLER;
++i;
writes[i].address = HW_CONTROL;
writes[i].value = a_priv->hw_control_bits;
@@ -781,7 +776,7 @@ static void agilent_82357a_request_system_control(gpib_board_t *board, int reque
retval = agilent_82357a_write_registers(a_priv, writes, i);
if (retval)
dev_err(&usb_dev->dev, "write_registers() returned error\n");
- return;// retval;
+ return retval;
}

static void agilent_82357a_interface_clear(gpib_board_t *board, int assert)
@@ -1584,7 +1579,7 @@ static int agilent_82357a_driver_resume(struct usb_interface *interface)
{
struct usb_device *usb_dev = interface_to_usbdev(interface);
gpib_board_t *board;
- int i, retval;
+ int i, retval = 0;

mutex_lock(&agilent_82357a_hotplug_lock);

@@ -1595,8 +1590,10 @@ static int agilent_82357a_driver_resume(struct usb_interface *interface)
break;
}
}
- if (i == MAX_NUM_82357A_INTERFACES)
+ if (i == MAX_NUM_82357A_INTERFACES) {
+ retval = -ENOENT;
goto resume_exit;
+ }

struct agilent_82357a_priv *a_priv = board->private_data;

@@ -1619,7 +1616,9 @@ static int agilent_82357a_driver_resume(struct usb_interface *interface)
return retval;
}
// set/unset system controller
- agilent_82357a_request_system_control(board, board->master);
+ retval = agilent_82357a_request_system_control(board, board->master);
+ if (retval)
+ goto resume_exit;
// toggle ifc if master
if (board->master) {
agilent_82357a_interface_clear(board, 1);
@@ -1637,7 +1636,7 @@ static int agilent_82357a_driver_resume(struct usb_interface *interface)
resume_exit:
mutex_unlock(&agilent_82357a_hotplug_lock);

- return 0;
+ return retval;
}

static struct usb_driver agilent_82357a_bus_driver = {
diff --git a/drivers/staging/gpib/cb7210/cb7210.c b/drivers/staging/gpib/cb7210/cb7210.c
index 19dfd8b4a8e7..1ad242d0e28e 100644
--- a/drivers/staging/gpib/cb7210/cb7210.c
+++ b/drivers/staging/gpib/cb7210/cb7210.c
@@ -577,7 +577,7 @@ static int cb7210_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void cb7210_request_system_control(gpib_board_t *board, int request_control)
+static int cb7210_request_system_control(gpib_board_t *board, int request_control)
{
struct cb7210_priv *priv = board->private_data;
struct nec7210_priv *nec_priv = &priv->nec7210_priv;
@@ -588,7 +588,7 @@ static void cb7210_request_system_control(gpib_board_t *board, int request_contr
priv->hs_mode_bits &= ~HS_SYS_CONTROL;

cb7210_write_byte(priv, priv->hs_mode_bits, HS_MODE);
- nec7210_request_system_control(board, nec_priv, request_control);
+ return nec7210_request_system_control(board, nec_priv, request_control);
}

static void cb7210_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/cec/cec_gpib.c b/drivers/staging/gpib/cec/cec_gpib.c
index 8f2b4b46a446..b34deeb68daf 100644
--- a/drivers/staging/gpib/cec/cec_gpib.c
+++ b/drivers/staging/gpib/cec/cec_gpib.c
@@ -82,11 +82,11 @@ static int cec_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void cec_request_system_control(gpib_board_t *board, int request_control)
+static int cec_request_system_control(gpib_board_t *board, int request_control)
{
struct cec_priv *priv = board->private_data;

- nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
+ return nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
}

static void cec_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/common/gpib_os.c b/drivers/staging/gpib/common/gpib_os.c
index 301c8a1a62c2..c9e097dcab37 100644
--- a/drivers/staging/gpib/common/gpib_os.c
+++ b/drivers/staging/gpib/common/gpib_os.c
@@ -1970,9 +1970,7 @@ static int request_system_control_ioctl(gpib_board_t *board, unsigned long arg)
if (retval)
return -EFAULT;

- ibrsc(board, request_control);
-
- return 0;
+ return ibrsc(board, request_control);
}

static int t1_delay_ioctl(gpib_board_t *board, unsigned long arg)
diff --git a/drivers/staging/gpib/common/iblib.c b/drivers/staging/gpib/common/iblib.c
index fd2874c2fff4..3d51a093fc8b 100644
--- a/drivers/staging/gpib/common/iblib.c
+++ b/drivers/staging/gpib/common/iblib.c
@@ -418,12 +418,19 @@ int ibsic(gpib_board_t *board, unsigned int usec_duration)
return 0;
}

- /* FIXME make int */
-void ibrsc(gpib_board_t *board, int request_control)
+int ibrsc(gpib_board_t *board, int request_control)
{
- board->master = request_control != 0;
+ int retval;
+
if (board->interface->request_system_control)
- board->interface->request_system_control(board, request_control);
+ retval = board->interface->request_system_control(board, request_control);
+ else
+ retval = -EPERM;
+
+ if (!retval)
+ board->master = request_control != 0;
+
+ return retval;
}

/*
diff --git a/drivers/staging/gpib/eastwood/fluke_gpib.c b/drivers/staging/gpib/eastwood/fluke_gpib.c
index 731732bd8301..a6ed93498c38 100644
--- a/drivers/staging/gpib/eastwood/fluke_gpib.c
+++ b/drivers/staging/gpib/eastwood/fluke_gpib.c
@@ -91,12 +91,12 @@ static int fluke_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void fluke_request_system_control(gpib_board_t *board, int request_control)
+static int fluke_request_system_control(gpib_board_t *board, int request_control)
{
struct fluke_priv *priv = board->private_data;
struct nec7210_priv *nec_priv = &priv->nec7210_priv;

- nec7210_request_system_control(board, nec_priv, request_control);
+ return nec7210_request_system_control(board, nec_priv, request_control);
}

static void fluke_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/fmh_gpib/fmh_gpib.c b/drivers/staging/gpib/fmh_gpib/fmh_gpib.c
index d62c83368518..946c00a5c7a5 100644
--- a/drivers/staging/gpib/fmh_gpib/fmh_gpib.c
+++ b/drivers/staging/gpib/fmh_gpib/fmh_gpib.c
@@ -82,12 +82,12 @@ static int fmh_gpib_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void fmh_gpib_request_system_control(gpib_board_t *board, int request_control)
+static int fmh_gpib_request_system_control(gpib_board_t *board, int request_control)
{
struct fmh_priv *priv = board->private_data;
struct nec7210_priv *nec_priv = &priv->nec7210_priv;

- nec7210_request_system_control(board, nec_priv, request_control);
+ return nec7210_request_system_control(board, nec_priv, request_control);
}

static void fmh_gpib_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/gpio/gpib_bitbang.c b/drivers/staging/gpib/gpio/gpib_bitbang.c
index 2012db188f58..30ffa54b8f96 100644
--- a/drivers/staging/gpib/gpio/gpib_bitbang.c
+++ b/drivers/staging/gpib/gpio/gpib_bitbang.c
@@ -855,6 +855,7 @@ static void set_atn(gpib_board_t *board, int atn_asserted)
priv->listener_state = listener_addressed;
if (priv->talker_state == talker_active)
priv->talker_state = talker_addressed;
+ SET_DIR_WRITE(priv); // need to be able to read bus NRFD/NDAC
} else {
if (priv->listener_state == listener_addressed) {
priv->listener_state = listener_active;
@@ -871,7 +872,6 @@ static int bb_take_control(gpib_board_t *board, int synchronous)
{
dbg_printk(2, "%d\n", synchronous);
set_atn(board, 1);
- set_bit(CIC_NUM, &board->status);
return 0;
}

@@ -882,16 +882,22 @@ static int bb_go_to_standby(gpib_board_t *board)
return 0;
}

-static void bb_request_system_control(gpib_board_t *board, int request_control)
+static int bb_request_system_control(gpib_board_t *board, int request_control)
{
+ struct bb_priv *priv = board->private_data;
+
dbg_printk(2, "%d\n", request_control);
if (request_control) {
- set_bit(CIC_NUM, &board->status);
- // drive DAV & EOI false, enable NRFD & NDAC irqs
- SET_DIR_WRITE(board->private_data);
+ gpiod_direction_output(REN, 1); /* user space must enable REN if needed */
+ gpiod_direction_output(IFC, 1); /* user space must toggle IFC if needed */
+ if (sn7516x)
+ gpiod_direction_output(DC, 0); /* enable ATN as output on SN75161/2 */
+ gpiod_direction_input(SRQ);
+ ENABLE_IRQ(priv->irq_SRQ, IRQ_TYPE_EDGE_FALLING);
} else {
- clear_bit(CIC_NUM, &board->status);
+ return -EPERM;
}
+ return 0;
}

static void bb_interface_clear(gpib_board_t *board, int assert)
@@ -903,6 +909,7 @@ static void bb_interface_clear(gpib_board_t *board, int assert)
gpiod_direction_output(IFC, 0);
priv->talker_state = talker_idle;
priv->listener_state = listener_idle;
+ set_bit(CIC_NUM, &board->status);
} else {
gpiod_direction_output(IFC, 1);
}
@@ -1293,8 +1300,6 @@ static int bb_attach(gpib_board_t *board, const gpib_board_config_t *config)
IRQF_TRIGGER_NONE))
goto bb_attach_fail_r;

- ENABLE_IRQ(priv->irq_SRQ, IRQ_TYPE_EDGE_FALLING);
-
dbg_printk(0, "attached board %d\n", board->minor);
goto bb_attach_out;

diff --git a/drivers/staging/gpib/hp_82335/hp82335.c b/drivers/staging/gpib/hp_82335/hp82335.c
index 982544d1b382..6d403a1422d7 100644
--- a/drivers/staging/gpib/hp_82335/hp82335.c
+++ b/drivers/staging/gpib/hp_82335/hp82335.c
@@ -67,11 +67,11 @@ static int hp82335_go_to_standby(gpib_board_t *board)
return tms9914_go_to_standby(board, &priv->tms9914_priv);
}

-static void hp82335_request_system_control(gpib_board_t *board, int request_control)
+static int hp82335_request_system_control(gpib_board_t *board, int request_control)
{
struct hp82335_priv *priv = board->private_data;

- tms9914_request_system_control(board, &priv->tms9914_priv, request_control);
+ return tms9914_request_system_control(board, &priv->tms9914_priv, request_control);
}

static void hp82335_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/hp_82341/hp_82341.c b/drivers/staging/gpib/hp_82341/hp_82341.c
index 91fbaf953bcd..0c03e8fedbb0 100644
--- a/drivers/staging/gpib/hp_82341/hp_82341.c
+++ b/drivers/staging/gpib/hp_82341/hp_82341.c
@@ -293,7 +293,7 @@ static int hp_82341_go_to_standby(gpib_board_t *board)
return tms9914_go_to_standby(board, &priv->tms9914_priv);
}

-static void hp_82341_request_system_control(gpib_board_t *board, int request_control)
+static int hp_82341_request_system_control(gpib_board_t *board, int request_control)
{
struct hp_82341_priv *priv = board->private_data;

@@ -302,7 +302,7 @@ static void hp_82341_request_system_control(gpib_board_t *board, int request_con
else
priv->mode_control_bits &= ~SYSTEM_CONTROLLER_BIT;
outb(priv->mode_control_bits, priv->iobase[0] + MODE_CONTROL_STATUS_REG);
- tms9914_request_system_control(board, &priv->tms9914_priv, request_control);
+ return tms9914_request_system_control(board, &priv->tms9914_priv, request_control);
}

static void hp_82341_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/include/gpib_proto.h b/drivers/staging/gpib/include/gpib_proto.h
index 1499f954210b..6448b5e77a01 100644
--- a/drivers/staging/gpib/include/gpib_proto.h
+++ b/drivers/staging/gpib/include/gpib_proto.h
@@ -38,7 +38,7 @@ int iblines(const gpib_board_t *board, short *lines);
int ibrd(gpib_board_t *board, uint8_t *buf, size_t length, int *end_flag, size_t *bytes_read);
int ibrpp(gpib_board_t *board, uint8_t *buf);
int ibrsv2(gpib_board_t *board, uint8_t status_byte, int new_reason_for_service);
-void ibrsc(gpib_board_t *board, int request_control);
+int ibrsc(gpib_board_t *board, int request_control);
int ibsic(gpib_board_t *board, unsigned int usec_duration);
int ibsre(gpib_board_t *board, int enable);
int ibpad(gpib_board_t *board, unsigned int addr);
diff --git a/drivers/staging/gpib/include/gpib_types.h b/drivers/staging/gpib/include/gpib_types.h
index b41781a55a60..f21942a03930 100644
--- a/drivers/staging/gpib/include/gpib_types.h
+++ b/drivers/staging/gpib/include/gpib_types.h
@@ -93,7 +93,7 @@ struct gpib_interface_struct {
*/
int (*go_to_standby)(gpib_board_t *board);
/* request/release control of the IFC and REN lines (system controller) */
- void (*request_system_control)(gpib_board_t *board, int request_control);
+ int (*request_system_control)(gpib_board_t *board, int request_control);
/* Asserts or de-asserts 'interface clear' (IFC) depending on
* boolean value of 'assert'
*/
diff --git a/drivers/staging/gpib/include/nec7210.h b/drivers/staging/gpib/include/nec7210.h
index ca998c4a84bf..05652bfa0bbf 100644
--- a/drivers/staging/gpib/include/nec7210.h
+++ b/drivers/staging/gpib/include/nec7210.h
@@ -86,8 +86,8 @@ int nec7210_command(gpib_board_t *board, struct nec7210_priv *priv, uint8_t *buf
size_t length, size_t *bytes_written);
int nec7210_take_control(gpib_board_t *board, struct nec7210_priv *priv, int syncronous);
int nec7210_go_to_standby(gpib_board_t *board, struct nec7210_priv *priv);
-void nec7210_request_system_control(gpib_board_t *board,
- struct nec7210_priv *priv, int request_control);
+int nec7210_request_system_control(gpib_board_t *board,
+ struct nec7210_priv *priv, int request_control);
void nec7210_interface_clear(gpib_board_t *board, struct nec7210_priv *priv, int assert);
void nec7210_remote_enable(gpib_board_t *board, struct nec7210_priv *priv, int enable);
int nec7210_enable_eos(gpib_board_t *board, struct nec7210_priv *priv, uint8_t eos_bytes,
diff --git a/drivers/staging/gpib/include/tms9914.h b/drivers/staging/gpib/include/tms9914.h
index d8c8d1c9b131..6da43f278aed 100644
--- a/drivers/staging/gpib/include/tms9914.h
+++ b/drivers/staging/gpib/include/tms9914.h
@@ -92,8 +92,8 @@ int tms9914_take_control(gpib_board_t *board, struct tms9914_priv *priv, int syn
int tms9914_take_control_workaround(gpib_board_t *board, struct tms9914_priv *priv,
int syncronous);
int tms9914_go_to_standby(gpib_board_t *board, struct tms9914_priv *priv);
-void tms9914_request_system_control(gpib_board_t *board, struct tms9914_priv *priv,
- int request_control);
+int tms9914_request_system_control(gpib_board_t *board, struct tms9914_priv *priv,
+ int request_control);
void tms9914_interface_clear(gpib_board_t *board, struct tms9914_priv *priv, int assert);
void tms9914_remote_enable(gpib_board_t *board, struct tms9914_priv *priv, int enable);
int tms9914_enable_eos(gpib_board_t *board, struct tms9914_priv *priv, uint8_t eos_bytes,
diff --git a/drivers/staging/gpib/ines/ines.h b/drivers/staging/gpib/ines/ines.h
index 3918737fa21a..12f4be7f6564 100644
--- a/drivers/staging/gpib/ines/ines.h
+++ b/drivers/staging/gpib/ines/ines.h
@@ -46,7 +46,7 @@ int ines_accel_write(gpib_board_t *board, uint8_t *buffer, size_t length,
int ines_command(gpib_board_t *board, uint8_t *buffer, size_t length, size_t *bytes_written);
int ines_take_control(gpib_board_t *board, int synchronous);
int ines_go_to_standby(gpib_board_t *board);
-void ines_request_system_control(gpib_board_t *board, int request_control);
+int ines_request_system_control(gpib_board_t *board, int request_control);
void ines_interface_clear(gpib_board_t *board, int assert);
void ines_remote_enable(gpib_board_t *board, int enable);
int ines_enable_eos(gpib_board_t *board, uint8_t eos_byte, int compare_8_bits);
diff --git a/drivers/staging/gpib/ines/ines_gpib.c b/drivers/staging/gpib/ines/ines_gpib.c
index 56da6cd91188..24fa7fc64d9d 100644
--- a/drivers/staging/gpib/ines/ines_gpib.c
+++ b/drivers/staging/gpib/ines/ines_gpib.c
@@ -440,11 +440,11 @@ int ines_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-void ines_request_system_control(gpib_board_t *board, int request_control)
+int ines_request_system_control(gpib_board_t *board, int request_control)
{
struct ines_priv *priv = board->private_data;

- nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
+ return nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
}

void ines_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c b/drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c
index 50faa0c17617..72cf2807b62e 100644
--- a/drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c
+++ b/drivers/staging/gpib/lpvo_usb_gpib/lpvo_usb_gpib.c
@@ -921,15 +921,17 @@ static void usb_gpib_remote_enable(gpib_board_t *board, int enable)

/* request_system_control */

-static void usb_gpib_request_system_control(gpib_board_t *board,
- int request_control)
+static int usb_gpib_request_system_control(gpib_board_t *board, int request_control)
{
- if (request_control)
- set_bit(CIC_NUM, &board->status);
+ int retval;
+
+ if (!request_control)
+ retval = -EPERM;
else
- clear_bit(CIC_NUM, &board->status);
+ retval = 0;
+ DIA_LOG(1, "done with %d -> retval %i\n", request_control, retval);

- DIA_LOG(1, "done with %d -> %lx\n", request_control, board->status);
+ return retval;
}

/* take_control */
diff --git a/drivers/staging/gpib/nec7210/nec7210.c b/drivers/staging/gpib/nec7210/nec7210.c
index 85f1e79d658a..a14211e54861 100644
--- a/drivers/staging/gpib/nec7210/nec7210.c
+++ b/drivers/staging/gpib/nec7210/nec7210.c
@@ -329,14 +329,15 @@ int nec7210_go_to_standby(gpib_board_t *board, struct nec7210_priv *priv)
}
EXPORT_SYMBOL(nec7210_go_to_standby);

-void nec7210_request_system_control(gpib_board_t *board, struct nec7210_priv *priv,
- int request_control)
+int nec7210_request_system_control(gpib_board_t *board, struct nec7210_priv *priv,
+ int request_control)
{
if (request_control == 0) {
write_byte(priv, AUX_CREN, AUXMR);
write_byte(priv, AUX_CIFC, AUXMR);
write_byte(priv, AUX_DSC, AUXMR);
}
+ return 0;
}
EXPORT_SYMBOL(nec7210_request_system_control);

diff --git a/drivers/staging/gpib/ni_usb/ni_usb_gpib.c b/drivers/staging/gpib/ni_usb/ni_usb_gpib.c
index 62fbc78204ce..969d88525e6e 100644
--- a/drivers/staging/gpib/ni_usb/ni_usb_gpib.c
+++ b/drivers/staging/gpib/ni_usb/ni_usb_gpib.c
@@ -1049,7 +1049,7 @@ static int ni_usb_go_to_standby(gpib_board_t *board)
return 0;
}

-static void ni_usb_request_system_control(gpib_board_t *board, int request_control)
+static int ni_usb_request_system_control(gpib_board_t *board, int request_control)
{
int retval;
struct ni_usb_priv *ni_priv = board->private_data;
@@ -1059,7 +1059,7 @@ static void ni_usb_request_system_control(gpib_board_t *board, int request_contr
unsigned int ibsta;

if (!ni_priv->bus_interface)
- return; // -ENODEV;
+ return -ENODEV;
usb_dev = interface_to_usbdev(ni_priv->bus_interface);
if (request_control) {
writes[i].device = NIUSB_SUBDEV_TNT4882;
@@ -1091,12 +1091,12 @@ static void ni_usb_request_system_control(gpib_board_t *board, int request_contr
retval = ni_usb_write_registers(ni_priv, writes, i, &ibsta);
if (retval < 0) {
dev_err(&usb_dev->dev, "register write failed, retval=%i\n", retval);
- return; // retval;
+ return retval;
}
if (!request_control)
ni_priv->ren_state = 0;
ni_usb_soft_update_status(board, ibsta, 0);
- return; // 0;
+ return 0;
}

//FIXME maybe the interface should have a "pulse interface clear" function that can return an error?
diff --git a/drivers/staging/gpib/pc2/pc2_gpib.c b/drivers/staging/gpib/pc2/pc2_gpib.c
index 6711851301ec..f9615b4a5fa2 100644
--- a/drivers/staging/gpib/pc2/pc2_gpib.c
+++ b/drivers/staging/gpib/pc2/pc2_gpib.c
@@ -127,11 +127,11 @@ static int pc2_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void pc2_request_system_control(gpib_board_t *board, int request_control)
+static int pc2_request_system_control(gpib_board_t *board, int request_control)
{
struct pc2_priv *priv = board->private_data;

- nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
+ return nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
}

static void pc2_interface_clear(gpib_board_t *board, int assert)
diff --git a/drivers/staging/gpib/tms9914/tms9914.c b/drivers/staging/gpib/tms9914/tms9914.c
index 1f2bb163cfb5..ab81020b6ebd 100644
--- a/drivers/staging/gpib/tms9914/tms9914.c
+++ b/drivers/staging/gpib/tms9914/tms9914.c
@@ -116,8 +116,8 @@ void tms9914_remote_enable(gpib_board_t *board, struct tms9914_priv *priv, int e
}
EXPORT_SYMBOL_GPL(tms9914_remote_enable);

-void tms9914_request_system_control(gpib_board_t *board, struct tms9914_priv *priv,
- int request_control)
+int tms9914_request_system_control(gpib_board_t *board, struct tms9914_priv *priv,
+ int request_control)
{
if (request_control) {
write_byte(priv, AUX_RQC, AUXCR);
@@ -125,6 +125,8 @@ void tms9914_request_system_control(gpib_board_t *board, struct tms9914_priv *pr
clear_bit(CIC_NUM, &board->status);
write_byte(priv, AUX_RLC, AUXCR);
}
+
+ return 0;
}
EXPORT_SYMBOL_GPL(tms9914_request_system_control);

diff --git a/drivers/staging/gpib/tnt4882/tnt4882_gpib.c b/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
index d32420dee5e5..e43f3d0b1945 100644
--- a/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
+++ b/drivers/staging/gpib/tnt4882/tnt4882_gpib.c
@@ -642,19 +642,21 @@ static int tnt4882_go_to_standby(gpib_board_t *board)
return nec7210_go_to_standby(board, &priv->nec7210_priv);
}

-static void tnt4882_request_system_control(gpib_board_t *board, int request_control)
+static int tnt4882_request_system_control(gpib_board_t *board, int request_control)
{
struct tnt4882_priv *priv = board->private_data;
+ int retval;

if (request_control) {
tnt_writeb(priv, SETSC, CMDR);
udelay(1);
}
- nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
+ retval = nec7210_request_system_control(board, &priv->nec7210_priv, request_control);
if (!request_control) {
tnt_writeb(priv, CLRSC, CMDR);
udelay(1);
}
+ return retval;
}

static void tnt4882_interface_clear(gpib_board_t *board, int assert)
--
2.48.1