~hc/RK356X_SDK_RELEASE.git

..	..	@@ -41,7 +41,7 @@
41	41
42	42	struct pwm_sifive_ddata {
43	43	struct pwm_chip chip;
44		- struct mutex lock; /* lock to protect user_count */
	44	+ struct mutex lock; /* lock to protect user_count and approx_period */
45	45	struct notifier_block notifier;
46	46	struct clk *clk;
47	47	void __iomem *regs;
..	..	@@ -76,6 +76,7 @@
76	76	mutex_unlock(&ddata->lock);
77	77	}
78	78
	79	+/* Called holding ddata->lock */
79	80	static void pwm_sifive_update_clock(struct pwm_sifive_ddata *ddata,
80	81	unsigned long rate)
81	82	{
..	..	@@ -163,7 +164,6 @@
163	164	return ret;
164	165	}
165	166
166		- mutex_lock(&ddata->lock);
167	167	cur_state = pwm->state;
168	168	enabled = cur_state.enabled;
169	169
..	..	@@ -182,14 +182,23 @@
182	182	/* The hardware cannot generate a 100% duty cycle */
183	183	frac = min(frac, (1U << PWM_SIFIVE_CMPWIDTH) - 1);
184	184
	185	+ mutex_lock(&ddata->lock);
185	186	if (state->period != ddata->approx_period) {
186		- if (ddata->user_count != 1) {
	187	+ /*
	188	+ * Don't let a 2nd user change the period underneath the 1st user.
	189	+ * However if ddate->approx_period == 0 this is the first time we set
	190	+ * any period, so let whoever gets here first set the period so other
	191	+ * users who agree on the period won't fail.
	192	+ */
	193	+ if (ddata->user_count != 1 && ddata->approx_period) {
	194	+ mutex_unlock(&ddata->lock);
187	195	ret = -EBUSY;
188	196	goto exit;
189	197	}
190	198	ddata->approx_period = state->period;
191	199	pwm_sifive_update_clock(ddata, clk_get_rate(ddata->clk));
192	200	}
	201	+ mutex_unlock(&ddata->lock);
193	202
194	203	writel(frac, ddata->regs + PWM_SIFIVE_PWMCMP(pwm->hwpwm));
195	204
..	..	@@ -198,7 +207,6 @@
198	207
199	208	exit:
200	209	clk_disable(ddata->clk);
201		- mutex_unlock(&ddata->lock);
202	210	return ret;
203	211	}
204	212
..	..	@@ -217,8 +225,11 @@
217	225	struct pwm_sifive_ddata *ddata =
218	226	container_of(nb, struct pwm_sifive_ddata, notifier);
219	227
220		- if (event == POST_RATE_CHANGE)
	228	+ if (event == POST_RATE_CHANGE) {
	229	+ mutex_lock(&ddata->lock);
221	230	pwm_sifive_update_clock(ddata, ndata->new_rate);
	231	+ mutex_unlock(&ddata->lock);
	232	+ }
222	233
223	234	return NOTIFY_OK;
224	235	}