[PATCH 4/4] counter: 104-quad-8: Utilize helper functions to handle PR, FLAG and PSC
From: William Breathitt Gray
Date: Sat Mar 18 2023 - 11:00:20 EST
The Preset Register (PR), Flag Register (FLAG), and Filter Clock
Prescaler (PSC) have common usage patterns. Wrap up such usage into
dedicated functions to improve code clarity.
Signed-off-by: William Breathitt Gray <william.gray@xxxxxxxxxx>
---
drivers/counter/104-quad-8.c | 103 +++++++++++++++--------------------
1 file changed, 45 insertions(+), 58 deletions(-)
diff --git a/drivers/counter/104-quad-8.c b/drivers/counter/104-quad-8.c
index 796f02fc53b8..27ec905ebe85 100644
--- a/drivers/counter/104-quad-8.c
+++ b/drivers/counter/104-quad-8.c
@@ -241,41 +241,49 @@ static int quad8_count_read(struct counter_device *counter,
return 0;
}
+static void quad8_preset_register_set(struct quad8 *const priv, const size_t id,
+ const unsigned long preset)
+{
+ struct channel_reg __iomem *const chan = priv->reg->channel + id;
+ int i;
+
+ /* Reset Byte Pointer */
+ iowrite8(SELECT_RLD | RESET_BP, &chan->control);
+
+ /* Set Preset Register */
+ for (i = 0; i < 3; i++)
+ iowrite8(preset >> (8 * i), &chan->data);
+}
+
+static void quad8_flag_register_reset(struct quad8 *const priv, const size_t id)
+{
+ struct channel_reg __iomem *const chan = priv->reg->channel + id;
+
+ /* Reset Borrow, Carry, Compare, and Sign flags */
+ iowrite8(SELECT_RLD | RESET_BT_CT_CPT_S_IDX, &chan->control);
+ /* Reset Error flag */
+ iowrite8(SELECT_RLD | RESET_E, &chan->control);
+}
+
static int quad8_count_write(struct counter_device *counter,
struct counter_count *count, u64 val)
{
struct quad8 *const priv = counter_priv(counter);
struct channel_reg __iomem *const chan = priv->reg->channel + count->id;
unsigned long irqflags;
- int i;
if (val > LS7267_CNTR_MAX)
return -ERANGE;
spin_lock_irqsave(&priv->lock, irqflags);
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
-
/* Counter can only be set via Preset Register */
- for (i = 0; i < 3; i++)
- iowrite8(val >> (8 * i), &chan->data);
-
+ quad8_preset_register_set(priv, count->id, val);
/* Transfer Preset Register to Counter */
iowrite8(SELECT_RLD | TRANSFER_PR_TO_CNTR, &chan->control);
-
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
-
+ quad8_flag_register_reset(priv, count->id);
/* Set Preset Register back to original value */
- val = priv->preset[count->id];
- for (i = 0; i < 3; i++)
- iowrite8(val >> (8 * i), &chan->data);
-
- /* Reset Borrow, Carry, Compare, and Sign flags */
- iowrite8(SELECT_RLD | RESET_BT_CT_CPT_S_IDX, &chan->control);
- /* Reset Error flag */
- iowrite8(SELECT_RLD | RESET_E, &chan->control);
+ quad8_preset_register_set(priv, count->id, priv->preset[count->id]);
spin_unlock_irqrestore(&priv->lock, irqflags);
@@ -791,22 +799,6 @@ static int quad8_count_preset_read(struct counter_device *counter,
return 0;
}
-static void quad8_preset_register_set(struct quad8 *const priv, const int id,
- const unsigned int preset)
-{
- struct channel_reg __iomem *const chan = priv->reg->channel + id;
- int i;
-
- priv->preset[id] = preset;
-
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
-
- /* Set Preset Register */
- for (i = 0; i < 3; i++)
- iowrite8(preset >> (8 * i), &chan->data);
-}
-
static int quad8_count_preset_write(struct counter_device *counter,
struct counter_count *count, u64 preset)
{
@@ -818,6 +810,7 @@ static int quad8_count_preset_write(struct counter_device *counter,
spin_lock_irqsave(&priv->lock, irqflags);
+ priv->preset[count->id] = preset;
quad8_preset_register_set(priv, count->id, preset);
spin_unlock_irqrestore(&priv->lock, irqflags);
@@ -864,6 +857,7 @@ static int quad8_count_ceiling_write(struct counter_device *counter,
switch (FIELD_GET(COUNT_MODE, priv->cmr[count->id])) {
case RANGE_LIMIT:
case MODULO_N:
+ priv->preset[count->id] = ceiling;
quad8_preset_register_set(priv, count->id, ceiling);
spin_unlock_irqrestore(&priv->lock, irqflags);
return 0;
@@ -985,25 +979,30 @@ static int quad8_signal_fck_prescaler_read(struct counter_device *counter,
return 0;
}
+static void quad8_filter_clock_prescaler_set(struct quad8 *const priv, const size_t id,
+ const u8 prescaler)
+{
+ struct channel_reg __iomem *const chan = priv->reg->channel + id;
+
+ /* Reset Byte Pointer */
+ iowrite8(SELECT_RLD | RESET_BP, &chan->control);
+ /* Reset filter clock factor */
+ iowrite8(prescaler, &chan->data);
+ iowrite8(SELECT_RLD | TRANSFER_PR0_TO_PSC, &chan->control);
+}
+
static int quad8_signal_fck_prescaler_write(struct counter_device *counter,
struct counter_signal *signal,
u8 prescaler)
{
struct quad8 *const priv = counter_priv(counter);
const size_t channel_id = signal->id / 2;
- struct channel_reg __iomem *const chan = priv->reg->channel + channel_id;
unsigned long irqflags;
spin_lock_irqsave(&priv->lock, irqflags);
priv->fck_prescaler[channel_id] = prescaler;
-
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
-
- /* Set filter clock factor */
- iowrite8(prescaler, &chan->data);
- iowrite8(SELECT_RLD | RESET_BP | TRANSFER_PR0_TO_PSC, &chan->control);
+ quad8_filter_clock_prescaler_set(priv, channel_id, prescaler);
spin_unlock_irqrestore(&priv->lock, irqflags);
@@ -1203,22 +1202,10 @@ static irqreturn_t quad8_irq_handler(int irq, void *private)
static void quad8_init_counter(struct quad8 *const priv, const size_t channel)
{
struct channel_reg __iomem *const chan = priv->reg->channel + channel;
- unsigned long i;
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
- /* Reset filter clock factor */
- iowrite8(0, &chan->data);
- iowrite8(SELECT_RLD | RESET_BP | TRANSFER_PR0_TO_PSC, &chan->control);
- /* Reset Byte Pointer */
- iowrite8(SELECT_RLD | RESET_BP, &chan->control);
- /* Reset Preset Register */
- for (i = 0; i < 3; i++)
- iowrite8(0x00, &chan->data);
- /* Reset Borrow, Carry, Compare, and Sign flags */
- iowrite8(SELECT_RLD | RESET_BT_CT_CPT_S_IDX, &chan->control);
- /* Reset Error flag */
- iowrite8(SELECT_RLD | RESET_E, &chan->control);
+ quad8_filter_clock_prescaler_set(priv, channel, 0);
+ quad8_preset_register_set(priv, channel, 0);
+ quad8_flag_register_reset(priv, channel);
/* Binary encoding; Normal count; non-quadrature mode */
priv->cmr[channel] = SELECT_CMR | BINARY | FIELD_PREP(COUNT_MODE, NORMAL_COUNT) |
--
2.39.2