| Message ID | 20230405125643.42398-1-andriy.shevchenko@linux.intel.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | [v2,1/1] i2c: mlxbf: Use readl_poll_timeout_atomic() for polling | expand |
Reviewed-by: Asmaa Mnebhi <asmaa@nvidia.com> > Subject: [PATCH v2 1/1] i2c: mlxbf: Use readl_poll_timeout_atomic() for > polling > > Convert the usage of an open-coded custom tight poll while loop with the > provided readl_poll_timeout_atomic() macro. > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > --- > v2: corrected comment (Asmaa) > drivers/i2c/busses/i2c-mlxbf.c | 106 ++++++++------------------------- > 1 file changed, 26 insertions(+), 80 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-mlxbf.c b/drivers/i2c/busses/i2c-mlxbf.c > index 1810d5791b3d..d9d4b65cb276 100644 > --- a/drivers/i2c/busses/i2c-mlxbf.c > +++ b/drivers/i2c/busses/i2c-mlxbf.c > @@ -12,6 +12,7 @@ > #include <linux/interrupt.h> > #include <linux/i2c.h> > #include <linux/io.h> > +#include <linux/iopoll.h> > #include <linux/kernel.h> > #include <linux/module.h> > #include <linux/mutex.h> > @@ -495,65 +496,6 @@ static u8 mlxbf_i2c_bus_count; > > static struct mutex mlxbf_i2c_bus_lock; > > -/* > - * Function to poll a set of bits at a specific address; it checks whether > - * the bits are equal to zero when eq_zero is set to 'true', and not equal > - * to zero when eq_zero is set to 'false'. > - * Note that the timeout is given in microseconds. > - */ > -static u32 mlxbf_i2c_poll(void __iomem *io, u32 addr, u32 mask, > - bool eq_zero, u32 timeout) > -{ > - u32 bits; > - > - timeout = (timeout / MLXBF_I2C_POLL_FREQ_IN_USEC) + 1; > - > - do { > - bits = readl(io + addr) & mask; > - if (eq_zero ? bits == 0 : bits != 0) > - return eq_zero ? 1 : bits; > - udelay(MLXBF_I2C_POLL_FREQ_IN_USEC); > - } while (timeout-- != 0); > - > - return 0; > -} > - > -/* > - * SW must make sure that the SMBus Master GW is idle before starting > - * a transaction. Accordingly, this function polls the Master FSM stop > - * bit; it returns false when the bit is asserted, true if not. > - */ > -static bool mlxbf_i2c_smbus_master_wait_for_idle(struct mlxbf_i2c_priv > *priv) -{ > - u32 mask = MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK; > - u32 addr = priv->chip->smbus_master_fsm_off; > - u32 timeout = MLXBF_I2C_SMBUS_TIMEOUT; > - > - if (mlxbf_i2c_poll(priv->mst->io, addr, mask, true, timeout)) > - return true; > - > - return false; > -} > - > -/* > - * wait for the lock to be released before acquiring it. > - */ > -static bool mlxbf_i2c_smbus_master_lock(struct mlxbf_i2c_priv *priv) -{ > - if (mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, > - MLXBF_I2C_MASTER_LOCK_BIT, true, > - MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT)) > - return true; > - > - return false; > -} > - > -static void mlxbf_i2c_smbus_master_unlock(struct mlxbf_i2c_priv *priv) -{ > - /* Clear the gw to clear the lock */ > - writel(0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); > -} > - > static bool mlxbf_i2c_smbus_transaction_success(u32 master_status, > u32 cause_status) > { > @@ -583,6 +525,7 @@ static int mlxbf_i2c_smbus_check_status(struct > mlxbf_i2c_priv *priv) { > u32 master_status_bits; > u32 cause_status_bits; > + u32 bits; > > /* > * GW busy bit is raised by the driver and cleared by the HW @@ - > 591,9 +534,9 @@ static int mlxbf_i2c_smbus_check_status(struct > mlxbf_i2c_priv *priv) > * then read the cause and master status bits to determine if > * errors occurred during the transaction. > */ > - mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, > - MLXBF_I2C_MASTER_BUSY_BIT, true, > - MLXBF_I2C_SMBUS_TIMEOUT); > + readl_poll_timeout_atomic(priv->mst->io + > MLXBF_I2C_SMBUS_MASTER_GW, > + bits, !(bits & > MLXBF_I2C_MASTER_BUSY_BIT), > + MLXBF_I2C_POLL_FREQ_IN_USEC, > MLXBF_I2C_SMBUS_TIMEOUT); > > /* Read cause status bits. */ > cause_status_bits = readl(priv->mst_cause->io + @@ -740,7 +683,8 > @@ mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, > u8 read_en, write_en, block_en, pec_en; > u8 slave, flags, addr; > u8 *read_buf; > - int ret = 0; > + u32 bits; > + int ret; > > if (request->operation_cnt > MLXBF_I2C_SMBUS_MAX_OP_CNT) > return -EINVAL; > @@ -760,11 +704,22 @@ mlxbf_i2c_smbus_start_transaction(struct > mlxbf_i2c_priv *priv, > * Try to acquire the smbus gw lock before any reads of the GW > register since > * a read sets the lock. > */ > - if (WARN_ON(!mlxbf_i2c_smbus_master_lock(priv))) > + ret = readl_poll_timeout_atomic(priv->mst->io + > MLXBF_I2C_SMBUS_MASTER_GW, > + bits, !(bits & > MLXBF_I2C_MASTER_LOCK_BIT), > + MLXBF_I2C_POLL_FREQ_IN_USEC, > + > MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT); > + if (WARN_ON(ret)) > return -EBUSY; > > - /* Check whether the HW is idle */ > - if (WARN_ON(!mlxbf_i2c_smbus_master_wait_for_idle(priv))) { > + /* > + * SW must make sure that the SMBus Master GW is idle before > starting > + * a transaction. Accordingly, this call polls the Master FSM stop bit; > + * it returns -ETIMEDOUT when the bit is asserted, 0 if not. > + */ > + ret = readl_poll_timeout_atomic(priv->mst->io + priv->chip- > >smbus_master_fsm_off, > + bits, !(bits & > MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK), > + MLXBF_I2C_POLL_FREQ_IN_USEC, > MLXBF_I2C_SMBUS_TIMEOUT); > + if (WARN_ON(ret)) { > ret = -EBUSY; > goto out_unlock; > } > @@ -855,7 +810,8 @@ mlxbf_i2c_smbus_start_transaction(struct > mlxbf_i2c_priv *priv, > } > > out_unlock: > - mlxbf_i2c_smbus_master_unlock(priv); > + /* Clear the gw to clear the lock */ > + writel(0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); > > return ret; > } > @@ -1835,18 +1791,6 @@ static bool mlxbf_i2c_has_coalesce(struct > mlxbf_i2c_priv *priv, bool *read, > return true; > } > > -static bool mlxbf_i2c_slave_wait_for_idle(struct mlxbf_i2c_priv *priv, > - u32 timeout) > -{ > - u32 mask = MLXBF_I2C_CAUSE_S_GW_BUSY_FALL; > - u32 addr = MLXBF_I2C_CAUSE_ARBITER; > - > - if (mlxbf_i2c_poll(priv->slv_cause->io, addr, mask, false, timeout)) > - return true; > - > - return false; > -} > - > static struct i2c_client *mlxbf_i2c_get_slave_from_addr( > struct mlxbf_i2c_priv *priv, u8 addr) { @@ -1949,7 > +1893,9 @@ static int mlxbf_i2c_irq_send(struct mlxbf_i2c_priv *priv, u8 > recv_bytes) > * Wait until the transfer is completed; the driver will wait > * until the GW is idle, a cause will rise on fall of GW busy. > */ > - mlxbf_i2c_slave_wait_for_idle(priv, MLXBF_I2C_SMBUS_TIMEOUT); > + readl_poll_timeout_atomic(priv->slv_cause->io + > MLXBF_I2C_CAUSE_ARBITER, > + data32, data32 & > MLXBF_I2C_CAUSE_S_GW_BUSY_FALL, > + MLXBF_I2C_POLL_FREQ_IN_USEC, > MLXBF_I2C_SMBUS_TIMEOUT); > > clear_csr: > /* Release the Slave GW. */ > -- > 2.40.0.1.gaa8946217a0b
On Wed, Apr 05, 2023 at 03:56:43PM +0300, Andy Shevchenko wrote: > Convert the usage of an open-coded custom tight poll while loop > with the provided readl_poll_timeout_atomic() macro. > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Applied to for-next, thanks!
diff --git a/drivers/i2c/busses/i2c-mlxbf.c b/drivers/i2c/busses/i2c-mlxbf.c index 1810d5791b3d..d9d4b65cb276 100644 --- a/drivers/i2c/busses/i2c-mlxbf.c +++ b/drivers/i2c/busses/i2c-mlxbf.c @@ -12,6 +12,7 @@ #include <linux/interrupt.h> #include <linux/i2c.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mutex.h> @@ -495,65 +496,6 @@ static u8 mlxbf_i2c_bus_count; static struct mutex mlxbf_i2c_bus_lock; -/* - * Function to poll a set of bits at a specific address; it checks whether - * the bits are equal to zero when eq_zero is set to 'true', and not equal - * to zero when eq_zero is set to 'false'. - * Note that the timeout is given in microseconds. - */ -static u32 mlxbf_i2c_poll(void __iomem *io, u32 addr, u32 mask, - bool eq_zero, u32 timeout) -{ - u32 bits; - - timeout = (timeout / MLXBF_I2C_POLL_FREQ_IN_USEC) + 1; - - do { - bits = readl(io + addr) & mask; - if (eq_zero ? bits == 0 : bits != 0) - return eq_zero ? 1 : bits; - udelay(MLXBF_I2C_POLL_FREQ_IN_USEC); - } while (timeout-- != 0); - - return 0; -} - -/* - * SW must make sure that the SMBus Master GW is idle before starting - * a transaction. Accordingly, this function polls the Master FSM stop - * bit; it returns false when the bit is asserted, true if not. - */ -static bool mlxbf_i2c_smbus_master_wait_for_idle(struct mlxbf_i2c_priv *priv) -{ - u32 mask = MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK; - u32 addr = priv->chip->smbus_master_fsm_off; - u32 timeout = MLXBF_I2C_SMBUS_TIMEOUT; - - if (mlxbf_i2c_poll(priv->mst->io, addr, mask, true, timeout)) - return true; - - return false; -} - -/* - * wait for the lock to be released before acquiring it. - */ -static bool mlxbf_i2c_smbus_master_lock(struct mlxbf_i2c_priv *priv) -{ - if (mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, - MLXBF_I2C_MASTER_LOCK_BIT, true, - MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT)) - return true; - - return false; -} - -static void mlxbf_i2c_smbus_master_unlock(struct mlxbf_i2c_priv *priv) -{ - /* Clear the gw to clear the lock */ - writel(0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); -} - static bool mlxbf_i2c_smbus_transaction_success(u32 master_status, u32 cause_status) { @@ -583,6 +525,7 @@ static int mlxbf_i2c_smbus_check_status(struct mlxbf_i2c_priv *priv) { u32 master_status_bits; u32 cause_status_bits; + u32 bits; /* * GW busy bit is raised by the driver and cleared by the HW @@ -591,9 +534,9 @@ static int mlxbf_i2c_smbus_check_status(struct mlxbf_i2c_priv *priv) * then read the cause and master status bits to determine if * errors occurred during the transaction. */ - mlxbf_i2c_poll(priv->mst->io, MLXBF_I2C_SMBUS_MASTER_GW, - MLXBF_I2C_MASTER_BUSY_BIT, true, - MLXBF_I2C_SMBUS_TIMEOUT); + readl_poll_timeout_atomic(priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW, + bits, !(bits & MLXBF_I2C_MASTER_BUSY_BIT), + MLXBF_I2C_POLL_FREQ_IN_USEC, MLXBF_I2C_SMBUS_TIMEOUT); /* Read cause status bits. */ cause_status_bits = readl(priv->mst_cause->io + @@ -740,7 +683,8 @@ mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, u8 read_en, write_en, block_en, pec_en; u8 slave, flags, addr; u8 *read_buf; - int ret = 0; + u32 bits; + int ret; if (request->operation_cnt > MLXBF_I2C_SMBUS_MAX_OP_CNT) return -EINVAL; @@ -760,11 +704,22 @@ mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, * Try to acquire the smbus gw lock before any reads of the GW register since * a read sets the lock. */ - if (WARN_ON(!mlxbf_i2c_smbus_master_lock(priv))) + ret = readl_poll_timeout_atomic(priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW, + bits, !(bits & MLXBF_I2C_MASTER_LOCK_BIT), + MLXBF_I2C_POLL_FREQ_IN_USEC, + MLXBF_I2C_SMBUS_LOCK_POLL_TIMEOUT); + if (WARN_ON(ret)) return -EBUSY; - /* Check whether the HW is idle */ - if (WARN_ON(!mlxbf_i2c_smbus_master_wait_for_idle(priv))) { + /* + * SW must make sure that the SMBus Master GW is idle before starting + * a transaction. Accordingly, this call polls the Master FSM stop bit; + * it returns -ETIMEDOUT when the bit is asserted, 0 if not. + */ + ret = readl_poll_timeout_atomic(priv->mst->io + priv->chip->smbus_master_fsm_off, + bits, !(bits & MLXBF_I2C_SMBUS_MASTER_FSM_STOP_MASK), + MLXBF_I2C_POLL_FREQ_IN_USEC, MLXBF_I2C_SMBUS_TIMEOUT); + if (WARN_ON(ret)) { ret = -EBUSY; goto out_unlock; } @@ -855,7 +810,8 @@ mlxbf_i2c_smbus_start_transaction(struct mlxbf_i2c_priv *priv, } out_unlock: - mlxbf_i2c_smbus_master_unlock(priv); + /* Clear the gw to clear the lock */ + writel(0, priv->mst->io + MLXBF_I2C_SMBUS_MASTER_GW); return ret; } @@ -1835,18 +1791,6 @@ static bool mlxbf_i2c_has_coalesce(struct mlxbf_i2c_priv *priv, bool *read, return true; } -static bool mlxbf_i2c_slave_wait_for_idle(struct mlxbf_i2c_priv *priv, - u32 timeout) -{ - u32 mask = MLXBF_I2C_CAUSE_S_GW_BUSY_FALL; - u32 addr = MLXBF_I2C_CAUSE_ARBITER; - - if (mlxbf_i2c_poll(priv->slv_cause->io, addr, mask, false, timeout)) - return true; - - return false; -} - static struct i2c_client *mlxbf_i2c_get_slave_from_addr( struct mlxbf_i2c_priv *priv, u8 addr) { @@ -1949,7 +1893,9 @@ static int mlxbf_i2c_irq_send(struct mlxbf_i2c_priv *priv, u8 recv_bytes) * Wait until the transfer is completed; the driver will wait * until the GW is idle, a cause will rise on fall of GW busy. */ - mlxbf_i2c_slave_wait_for_idle(priv, MLXBF_I2C_SMBUS_TIMEOUT); + readl_poll_timeout_atomic(priv->slv_cause->io + MLXBF_I2C_CAUSE_ARBITER, + data32, data32 & MLXBF_I2C_CAUSE_S_GW_BUSY_FALL, + MLXBF_I2C_POLL_FREQ_IN_USEC, MLXBF_I2C_SMBUS_TIMEOUT); clear_csr: /* Release the Slave GW. */
Convert the usage of an open-coded custom tight poll while loop with the provided readl_poll_timeout_atomic() macro. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> --- v2: corrected comment (Asmaa) drivers/i2c/busses/i2c-mlxbf.c | 106 ++++++++------------------------- 1 file changed, 26 insertions(+), 80 deletions(-)