diff options
| author | Richard Fitzgerald <rf@opensource.cirrus.com> | 2023-03-15 15:50:51 +0100 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2023-04-12 12:00:35 +0200 |
| commit | 9ddae9dad09e8bdaa33909bdcbb062c883c3c332 (patch) | |
| tree | 81f67cde2e1f44a79aa66fb7a241727fa027e83e | |
| parent | soundwire: qcom: gracefully handle too many ports in DT (diff) | |
| download | linux-9ddae9dad09e8bdaa33909bdcbb062c883c3c332.tar.xz linux-9ddae9dad09e8bdaa33909bdcbb062c883c3c332.zip | |
soundwire: bandwidth allocation: Use hweight32() to calculate set bits
Replace the call to sdw_ch_mask_to_ch() with a call to hweight32().
sdw_ch_mask_to_ch() is counting the number of set bits. The hweight()
family of functions already do this, and they have an advantage of
using a bit-counting instruction if it is available on the target CPU.
This also fixes a potential infinite loop bug in the implementation of
sdw_ch_mask_to_ch().
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230315145051.2299822-1-rf@opensource.cirrus.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/soundwire/bus.h | 11 | ||||
| -rw-r--r-- | drivers/soundwire/generic_bandwidth_allocation.c | 3 |
2 files changed, 2 insertions, 12 deletions
diff --git a/drivers/soundwire/bus.h b/drivers/soundwire/bus.h index 96927a143796..f0a59e5df631 100644 --- a/drivers/soundwire/bus.h +++ b/drivers/soundwire/bus.h @@ -158,17 +158,6 @@ int sdw_transfer_defer(struct sdw_bus *bus, struct sdw_msg *msg); int sdw_fill_msg(struct sdw_msg *msg, struct sdw_slave *slave, u32 addr, size_t count, u16 dev_num, u8 flags, u8 *buf); -/* Retrieve and return channel count from channel mask */ -static inline int sdw_ch_mask_to_ch(int ch_mask) -{ - int c = 0; - - for (c = 0; ch_mask; ch_mask >>= 1) - c += ch_mask & 1; - - return c; -} - /* Fill transport parameter data structure */ static inline void sdw_fill_xport_params(struct sdw_transport_params *params, int port_num, bool grp_ctrl_valid, diff --git a/drivers/soundwire/generic_bandwidth_allocation.c b/drivers/soundwire/generic_bandwidth_allocation.c index f7c66083a4dd..ea3e8ef408e4 100644 --- a/drivers/soundwire/generic_bandwidth_allocation.c +++ b/drivers/soundwire/generic_bandwidth_allocation.c @@ -6,6 +6,7 @@ * */ +#include <linux/bitops.h> #include <linux/device.h> #include <linux/module.h> #include <linux/mod_devicetable.h> @@ -54,7 +55,7 @@ static void sdw_compute_slave_ports(struct sdw_master_runtime *m_rt, slave_total_ch = 0; list_for_each_entry(p_rt, &s_rt->port_list, port_node) { - ch = sdw_ch_mask_to_ch(p_rt->ch_mask); + ch = hweight32(p_rt->ch_mask); sdw_fill_xport_params(&p_rt->transport_params, p_rt->num, false, |