1 // SPDX-License-Identifier: GPL-2.0
3  * Copyright (c) 2011-2017, The Linux Foundation
10  * slim_ctrl_clk_pause() - Called by slimbus controller to enter/exit
17  * Slimbus specification needs this sequence to turn-off clocks for the bus.
20  * To exit clock-pause, controller typically wakes up active framer device.
23  * For entering clock-pause, -EBUSY is returned if a message txn in pending.
29 	struct slim_sched *sched = &ctrl->sched;  in slim_ctrl_clk_pause()
36 		return -EINVAL;  in slim_ctrl_clk_pause()
38 	mutex_lock(&sched->m_reconf);  in slim_ctrl_clk_pause()
40 		if (sched->clk_state == SLIM_CLK_ACTIVE) {  in slim_ctrl_clk_pause()
41 			mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()
46 		 * Fine-tune calculation based on clock gear,  in slim_ctrl_clk_pause()
47 		 * message-bandwidth after bandwidth management  in slim_ctrl_clk_pause()
49 		ret = wait_for_completion_timeout(&sched->pause_comp,  in slim_ctrl_clk_pause()
52 			mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()
54 			return -ETIMEDOUT;  in slim_ctrl_clk_pause()
63 		if (sched->clk_state == SLIM_CLK_PAUSED && ctrl->wakeup)  in slim_ctrl_clk_pause()
64 			ret = ctrl->wakeup(ctrl);  in slim_ctrl_clk_pause()
66 			sched->clk_state = SLIM_CLK_ACTIVE;  in slim_ctrl_clk_pause()
67 		mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()
73 	if (ctrl->sched.clk_state == SLIM_CLK_PAUSED) {  in slim_ctrl_clk_pause()
74 		mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()
78 	spin_lock_irqsave(&ctrl->txn_lock, flags);  in slim_ctrl_clk_pause()
81 		if (idr_find(&ctrl->tid_idr, i)) {  in slim_ctrl_clk_pause()
82 			spin_unlock_irqrestore(&ctrl->txn_lock, flags);  in slim_ctrl_clk_pause()
83 			mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()
84 			return -EBUSY;  in slim_ctrl_clk_pause()
87 	spin_unlock_irqrestore(&ctrl->txn_lock, flags);  in slim_ctrl_clk_pause()
89 	sched->clk_state = SLIM_CLK_ENTERING_PAUSE;  in slim_ctrl_clk_pause()
112 		sched->clk_state = SLIM_CLK_ACTIVE;  in slim_ctrl_clk_pause()
114 		sched->clk_state = SLIM_CLK_PAUSED;  in slim_ctrl_clk_pause()
115 		complete(&sched->pause_comp);  in slim_ctrl_clk_pause()
117 	mutex_unlock(&sched->m_reconf);  in slim_ctrl_clk_pause()