forked from Minki/linux
588eb93ea4
In our former i2c driver, i2c clk is enabled and disabled in xfer function, which contributes to power saving. However, the clk enable process brings a busy wait delay until the core is stable. As a result, the performance is sacrificed. To weigh the power consumption and i2c bus performance, runtime pm is the good solution for it. The clk is enabled when a i2c transfer starts, and disabled after a specifically defined delay. If CONFIG_PM is disabled the net result of this patch is that the clock is never disabled. Without the patch the test case (many eeprom reads) executes with approx: real 1m7.735s user 0m0.488s sys 0m20.040s With the patch the same test case (many eeprom reads) executes with approx: real 0m54.241s user 0m0.440s sys 0m5.920s Signed-off-by: Fugang Duan <B38611@freescale.com> Signed-off-by: Gao Pan <b54642@freescale.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> [wsa: sorted includes] Signed-off-by: Wolfram Sang <wsa@the-dreams.de> |
||
|---|---|---|
| .. | ||
| algos | ||
| busses | ||
| muxes | ||
| i2c-boardinfo.c | ||
| i2c-core.c | ||
| i2c-core.h | ||
| i2c-dev.c | ||
| i2c-mux.c | ||
| i2c-slave-eeprom.c | ||
| i2c-smbus.c | ||
| i2c-stub.c | ||
| Kconfig | ||
| Makefile | ||