Commits
Robin Gong committed 2542a23d944
MLK-14241-1 regulator: pf1550-regulator-rpmsg: add mutex for pm_qos_add_request reentry Multi drivers(mmc, cpufreq..) may access pf1550 regulator rpmsg driver at the same time, so we have to add mutex for this multi-entry case. Otherwise the below kernel warning maybe triggered: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 19 at kernel/power/qos.c:453 pf1550_send_message+0x4c/0xf8() pm_qos_add_request() called for already added request Modules linked in: CPU: 0 PID: 19 Comm: kworker/0:1 Not tainted 4.1.33-02293-g80b8c19 #636 Hardware name: Freescale i.MX7ULP (Device Tree) Workqueue: events od_dbs_timer [<80015d78>] (unwind_backtrace) from [<8001271c>] (show_stack+0x10/0x14) [<8001271c>] (show_stack) from [<8082ba50>] (dump_stack+0x88/0x9c) [<8082ba50>] (dump_stack) from [<800387c8>] (warn_slowpath_common+0x80/0xb0) [<800387c8>] (warn_slowpath_common) from [<80038828>] (warn_slowpath_fmt+0x30/0x40) [<80038828>] (warn_slowpath_fmt) from [<80341180>] (pf1550_send_message+0x4c/0xf8) [<80341180>] (pf1550_send_message) from [<80341504>] (pf1550_get_voltage+0x48/0x5c) [<80341504>] (pf1550_get_voltage) from [<803370a0>] (_regulator_get_voltage+0x68/0xb4) [<803370a0>] (_regulator_get_voltage) from [<8033936c>] (_regulator_do_set_voltage+0x5c/0x3e4) [<8033936c>] (_regulator_do_set_voltage) from [<803397a4>] (regulator_set_voltage+0xb0/0x14c) [<803397a4>] (regulator_set_voltage) from [<8058dae8>] (imx7ulp_set_target+0x178/0x238) [<8058dae8>] (imx7ulp_set_target) from [<80584d14>] (__cpufreq_driver_target+0x164/0x294) [<80584d14>] (__cpufreq_driver_target) from [<8058bb08>] (dbs_check_cpu+0x1a0/0x1e0) [<8058bb08>] (dbs_check_cpu) from [<805888e8>] (od_dbs_timer+0x80/0x138) [<805888e8>] (od_dbs_timer) from [<8004bbbc>] (process_one_work+0x118/0x3e4) [<8004bbbc>] (process_one_work) from [<8004bed4>] (worker_thread+0x4c/0x4f4) [<8004bed4>] (worker_thread) from [<80050e4c>] (kthread+0xdc/0xf4) [<80050e4c>] (kthread) from [<8000f528>] (ret_from_fork+0x14/0x2c) ---[ end trace f8281ecde7a0b4ce ]--- ------------[ cut here ]------------ Signed-off-by: Robin Gong <yibin.gong@nxp.com>