C++ clk_get_rate函数代码示例

static int gpu_set_clock(struct exynos_context *platform, int clk)
{
	long g3d_rate_prev = -1;
	unsigned long g3d_rate = clk * MHZ;
	int ret = 0;
	int level = 0;

	if (aclk_g3d == 0)
		return -1;

#ifdef CONFIG_MALI_RT_PM
	if (platform->exynos_pm_domain)
		mutex_lock(&platform->exynos_pm_domain->access_lock);
#endif /* CONFIG_MALI_RT_PM */

	if (!gpu_is_power_on()) {
		ret = -1;
		GPU_LOG(DVFS_INFO, DUMMY, 0u, 0u, "%s: can't set clock in the power-off state!\n", __func__);
		goto err;
	}

	g3d_rate_prev = clk_get_rate(aclk_g3d);

	/* if changed the VPLL rate, set rate for VPLL and wait for lock time */
	if (g3d_rate != g3d_rate_prev) {

		ret = clk_set_parent(mout_g3d, fin_pll);
		if (ret < 0) {
			GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "%s: failed to clk_set_parent [fin_pll]\n", __func__);
			goto err;
		}

		/*change g3d pll*/
		ret = clk_set_rate(fout_g3d_pll, g3d_rate);
		if (ret < 0) {
			GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "%s: failed to clk_set_rate [fout_g3d_pll]\n", __func__);
			goto err;
		}

		level = gpu_dvfs_get_level(g3d_rate/MHZ);
		if (level < 0) {
			GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "%s: failed to gpu_dvfs_get_level \n", __func__);
			goto err;
		}

		ret = clk_set_rate(sclk_hpm_g3d, (clk_get_rate(aclk_g3d)/hpm_freq_table[level]));
		if(ret < 0)
			GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "%s: failed to clk_set_rate [sclk_hpm_g3d]\n", __func__);

		ret = clk_set_parent(mout_g3d, fout_g3d_pll);
		if (ret < 0) {
			GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "%s: failed to clk_set_parent [fout_g3d_pll]\n", __func__);
			goto err;
		}

		g3d_rate_prev = g3d_rate;
	}

	platform->cur_clock = gpu_get_cur_clock(platform);

	if (platform->cur_clock != clk_get_rate(fout_g3d_pll)/MHZ)
		GPU_LOG(DVFS_ERROR, DUMMY, 0u, 0u, "clock value is wrong (aclk_g3d: %d, fout_g3d_pll: %d)\n",
				platform->cur_clock, (int) clk_get_rate(fout_g3d_pll)/MHZ);
	GPU_LOG(DVFS_DEBUG, LSI_CLOCK_VALUE, g3d_rate/MHZ, platform->cur_clock,
		"clock set: %ld, clock get: %d\n", g3d_rate/MHZ, platform->cur_clock);
err:
#ifdef CONFIG_MALI_RT_PM
	if (platform->exynos_pm_domain)
		mutex_unlock(&platform->exynos_pm_domain->access_lock);
#endif /* CONFIG_MALI_RT_PM */
	return ret;
}

static int serial_pxa_startup(struct uart_port *port)
{
	struct uart_pxa_port *up = (struct uart_pxa_port *)port;
	unsigned long flags;
	int retval;

	if (port->line == 3) /* HWUART */
		up->mcr |= UART_MCR_AFE;
	else
		up->mcr = 0;

	up->port.uartclk = clk_get_rate(up->clk);

	/*
	 * Allocate the IRQ
	 */
	retval = request_irq(up->port.irq, serial_pxa_irq, 0, up->name, up);
	if (retval)
		return retval;

	/*
	 * Clear the FIFO buffers and disable them.
	 * (they will be reenabled in set_termios())
	 */
	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
	serial_out(up, UART_FCR, 0);

	/*
	 * Clear the interrupt registers.
	 */
	(void) serial_in(up, UART_LSR);
	(void) serial_in(up, UART_RX);
	(void) serial_in(up, UART_IIR);
	(void) serial_in(up, UART_MSR);

	/*
	 * Now, initialize the UART
	 */
	serial_out(up, UART_LCR, UART_LCR_WLEN8);

	spin_lock_irqsave(&up->port.lock, flags);
	up->port.mctrl |= TIOCM_OUT2;
	serial_pxa_set_mctrl(&up->port, up->port.mctrl);
	spin_unlock_irqrestore(&up->port.lock, flags);

	/*
	 * Finally, enable interrupts.  Note: Modem status interrupts
	 * are set via set_termios(), which will be occurring imminently
	 * anyway, so we don't enable them here.
	 */
	up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
	serial_out(up, UART_IER, up->ier);

	/*
	 * And clear the interrupt registers again for luck.
	 */
	(void) serial_in(up, UART_LSR);
	(void) serial_in(up, UART_RX);
	(void) serial_in(up, UART_IIR);
	(void) serial_in(up, UART_MSR);

	return 0;
}

/*
 * To avoid duplicating clock code, allow machine driver to
 * get the clockrate from here.
 */
u32 s3c24xx_i2s_get_clockrate(void)
{
	return clk_get_rate(s3c24xx_i2s.iis_clk);
}

int __init exynos_cpufreq_cluster1_init(struct exynos_dvfs_info *info)
{
	unsigned long rate;
	struct device_node *pmic_node;
	int ret, tmp;

	set_volt_table_CA57();

	mout_atlas_pll = clk_get(NULL, "mout_atlas_pll");
	if (IS_ERR(mout_atlas_pll)) {
		pr_err("failed get mout_atlas_pll clk\n");
		goto err_mout_atlas_pll;
	}

	mout_atlas = clk_get(NULL, "mout_atlas");
	if (IS_ERR(mout_atlas)) {
		pr_err("failed get mout_atlas clk\n");
		goto err_mout_atlas;
	}

	if (clk_set_parent(mout_atlas, mout_atlas_pll)) {
		pr_err("Unable to set parent %s of clock %s.\n",
				mout_atlas_pll->name, mout_atlas->name);
		goto err_clk_set_parent_atlas;
	}

	mout_bus0_pll_atlas = clk_get(NULL, "mout_bus0_pll_atlas");
	if (IS_ERR(mout_bus0_pll_atlas)) {
		pr_err("failed get mout_bus0_pll_atlas clk\n");
		goto err_mout_bus0_pll_atlas;
	}

	if (clk_prepare_enable(mout_atlas_pll) || clk_prepare_enable(mout_atlas)) {
		pr_err("Unable to enable Atlas clocks \n");
		goto err_clk_prepare_enable;
	}

	rate = clk_get_rate(mout_bus0_pll_atlas) / 1000;

	info->mpll_freq_khz = rate;
	info->pll_safe_idx = L17;
	info->max_support_idx = max_support_idx_CA57;
	info->min_support_idx = min_support_idx_CA57;

	/* booting frequency is 1.7GHz */
	info->boot_cpu_min_qos = exynos7420_freq_table_CA57[L8].frequency;
	info->boot_cpu_max_qos = exynos7420_freq_table_CA57[L8].frequency;
#ifdef CONFIG_SEC_PM
	/* booting max frequency is 1.5GHz when JIG cable is attached */
	info->jig_boot_cpu_max_qos = exynos7420_freq_table_CA57[L10].frequency;

	/* This low freq used for FOTA(dex2oat) update */
	info->low_boot_cpu_max_qos = exynos7420_freq_table_CA57[L12].frequency;
#endif
#if defined(CONFIG_PMU_COREMEM_RATIO)
	info->region_bus_table = exynos7420_region_bus_table_CA57;
#else
 	info->bus_table = exynos7420_bus_table_CA57;
#endif
	info->cpu_clk = mout_atlas_pll;

	/* reboot limit frequency is 800MHz */
	info->reboot_limit_freq = exynos7420_freq_table_CA57[L17].frequency;

	info->volt_table = exynos7420_volt_table_CA57;
	info->abb_table = NULL; //exynos7420_abb_table_CA57;
	info->freq_table = exynos7420_freq_table_CA57;
	info->set_freq = exynos7420_set_frequency_CA57;
	info->need_apll_change = exynos7420_pms_change_CA57;
	info->is_alive = exynos7420_is_alive_CA57;
	info->set_ema = exynos7420_set_ema_CA57;

	pmic_node = of_find_compatible_node(NULL, NULL, "samsung,s2mps15-pmic");

	if (!pmic_node) {
		pr_err("%s: faile to get pmic dt_node\n", __func__);
	} else {
		ret = of_property_read_u32(pmic_node, "smpl_warn_en", &en_smpl_warn);
		if (ret)
			pr_err("%s: faile to get Property of smpl_warn_en\n", __func__);
	}

	if (en_smpl_warn) {
		info->check_smpl = exynos7420_check_smpl_CA57;

		/* ATLAS_RATIO_SMPL */
		tmp = __raw_readl(EXYNOS7420_ATLAS_SMPL_CTRL0);
		tmp &= 0x7F;
		tmp |= 0x44;
		__raw_writel(tmp, EXYNOS7420_ATLAS_SMPL_CTRL0);
		pr_info("%s SMPL_WARN ENABLE (DIV:%d) ", __func__, tmp&0x3F);

		exynos_cpufreq_smpl_warn_register_notifier(&exynos7420_cpufreq_smpl_warn_notifier);
	}

	return 0;

err_clk_prepare_enable:
err_mout_bus0_pll_atlas:
err_clk_set_parent_atlas:
//.........这里部分代码省略.........

static unsigned long blizzard_get_clock_rate(void)
{
	return clk_get_rate(blizzard.sys_ck);
}

static int rk29_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct snd_soc_dai *codec_dai = rtd->codec_dai;
	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
	unsigned int pll_out = 0, dai_fmt = rtd->dai_link->dai_fmt;
	int div_bclk,div_mclk;
	int ret;
	struct clk	*general_pll;

	DBG("Enter::%s----%d\n", __FUNCTION__, __LINE__);

	/* set codec DAI configuration */
	ret = snd_soc_dai_set_fmt(codec_dai, dai_fmt);
	if (ret < 0) {
		printk("%s():failed to set the format for codec side\n", __FUNCTION__);
		return ret;
	}

	/* set cpu DAI configuration */
	ret = snd_soc_dai_set_fmt(cpu_dai, dai_fmt);
	if (ret < 0) {
		printk("%s():failed to set the format for cpu side\n", __FUNCTION__);
		return ret;
	}

        switch(params_rate(params)) {
        case 8000:
        case 16000:
        case 24000:
        case 32000:
        case 48000:
                pll_out = 12288000;
                break;
        case 11025:
        case 22050:
        case 44100:
                pll_out = 11289600;
                break;
        default:
                DBG("Enter:%s, %d, Error rate=%d\n",__FUNCTION__,__LINE__,params_rate(params));
                return -EINVAL;
                break;
        }
        DBG("Enter:%s, %d, rate=%d\n",__FUNCTION__,__LINE__,params_rate(params));

        //pll_out = 12000000;
        //snd_soc_dai_set_pll(codec_dai, NULL, 12000000, pll_out);
        snd_soc_dai_set_clkdiv(codec_dai, WM8900_LRCLK_MODE, 0x000);

	if ((dai_fmt & SND_SOC_DAIFMT_MASTER_MASK) == SND_SOC_DAIFMT_CBM_CFM) {
		snd_soc_dai_set_clkdiv(codec_dai, WM8900_BCLK_DIV, WM8900_BCLK_DIV_4);
		snd_soc_dai_set_clkdiv(codec_dai, WM8900_DAC_LRCLK,(pll_out/4)/params_rate(params));
		snd_soc_dai_set_clkdiv(codec_dai, WM8900_ADC_LRCLK,(pll_out/4)/params_rate(params));
	} else {
		general_pll=clk_get(NULL, "general_pll");
		if(clk_get_rate(general_pll)>260000000)
		{
			div_bclk=(pll_out/4)/params_rate(params)-1;
			div_mclk=3;
		}
		else if(clk_get_rate(general_pll)>130000000)
		{
			div_bclk=(pll_out/2)/params_rate(params)-1;
			div_mclk=1;
		}
		else
		{
			pll_out=pll_out/4;
			div_bclk=(pll_out)/params_rate(params)-1;
			div_mclk=0;
		}
		DBG("func is%s,gpll=%ld,pll_out=%u,div_mclk=%d\n",
			__FUNCTION__,clk_get_rate(general_pll),pll_out,div_mclk);
		snd_soc_dai_set_sysclk(cpu_dai, 0, pll_out, 0);
        snd_soc_dai_set_clkdiv(cpu_dai, ROCKCHIP_DIV_BCLK,div_bclk);
        snd_soc_dai_set_clkdiv(cpu_dai, ROCKCHIP_DIV_MCLK, div_mclk);
	}
        DBG("Enter:%s, %d, LRCK=%d\n",__FUNCTION__,__LINE__,(pll_out/4)/params_rate(params));
        
        return 0;
}

void __init s3c2443_init_clocks(int xtal)
{
	struct clk *clkp;
	unsigned long epllcon = __raw_readl(S3C2443_EPLLCON);
	int ret;
	int ptr;

	/* s3c2443 parents h and p clocks from prediv */
	clk_h.parent = &clk_prediv;
	clk_p.parent = &clk_prediv;

	s3c24xx_register_baseclocks(xtal);
	s3c2443_setup_clocks();
	s3c2443_clk_initparents();

	for (ptr = 0; ptr < ARRAY_SIZE(clks); ptr++) {
		clkp = clks[ptr];

		ret = s3c24xx_register_clock(clkp);
		if (ret < 0) {
			printk(KERN_ERR "Failed to register clock %s (%d)\n",
			       clkp->name, ret);
		}
	}

	clk_epll.rate = s3c2443_get_epll(epllcon, xtal);
	clk_epll.parent = &clk_epllref;
	clk_usb_bus.parent = &clk_usb_bus_host;

	/* ensure usb bus clock is within correct rate of 48MHz */

	if (clk_get_rate(&clk_usb_bus_host) != (48 * 1000 * 1000)) {
		printk(KERN_INFO "Warning: USB host bus not at 48MHz\n");
		clk_set_rate(&clk_usb_bus_host, 48*1000*1000);
	}

	printk("S3C2443: epll %s %ld.%03ld MHz, usb-bus %ld.%03ld MHz\n",
	       (epllcon & S3C2443_PLLCON_OFF) ? "off":"on",
	       print_mhz(clk_get_rate(&clk_epll)),
	       print_mhz(clk_get_rate(&clk_usb_bus)));

	/* register clocks from clock array */

	s3c_register_clocks(init_clocks, ARRAY_SIZE(init_clocks));

	/* We must be careful disabling the clocks we are not intending to
	 * be using at boot time, as subsystems such as the LCD which do
	 * their own DMA requests to the bus can cause the system to lockup
	 * if they where in the middle of requesting bus access.
	 *
	 * Disabling the LCD clock if the LCD is active is very dangerous,
	 * and therefore the bootloader should be careful to not enable
	 * the LCD clock if it is not needed.
	*/

	/* install (and disable) the clocks we do not need immediately */

	clkp = init_clocks_disable;
	for (ptr = 0; ptr < ARRAY_SIZE(init_clocks_disable); ptr++, clkp++) {

		ret = s3c24xx_register_clock(clkp);
		if (ret < 0) {
			printk(KERN_ERR "Failed to register clock %s (%d)\n",
			       clkp->name, ret);
		}

		(clkp->enable)(clkp, 0);
	}

	s3c_pwmclk_init();
}

static unsigned long spdif_clk_get_rate(struct clk *clk)
{
	return clk_get_rate(clk->parent) / 4;
}

static inline unsigned long fec_clk_get_rate(struct fec_priv *fec)
{
	return clk_get_rate(fec->clk);
}

//.........这里部分代码省略.........

	for (i = 0; i < master->num_chipselect; i++) {
		int cs_gpio = of_get_named_gpio(np, "cs-gpios", i);
		if (!gpio_is_valid(cs_gpio) && mxc_platform_info)
			cs_gpio = mxc_platform_info->chipselect[i];

		spi_imx->chipselect[i] = cs_gpio;
		if (!gpio_is_valid(cs_gpio))
			continue;

		ret = devm_gpio_request(&pdev->dev, spi_imx->chipselect[i],
					DRIVER_NAME);
		if (ret) {
			dev_err(&pdev->dev, "can't get cs gpios\n");
			goto out_master_put;
		}
	}

	spi_imx->bitbang.chipselect = spi_imx_chipselect;
	spi_imx->bitbang.setup_transfer = spi_imx_setupxfer;
	spi_imx->bitbang.txrx_bufs = spi_imx_transfer;
	spi_imx->bitbang.master->setup = spi_imx_setup;
	spi_imx->bitbang.master->cleanup = spi_imx_cleanup;
	spi_imx->bitbang.master->prepare_message = spi_imx_prepare_message;
	spi_imx->bitbang.master->unprepare_message = spi_imx_unprepare_message;
	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;

	init_completion(&spi_imx->xfer_done);

	spi_imx->devtype_data = of_id ? of_id->data :
		(struct spi_imx_devtype_data *) pdev->id_entry->driver_data;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	spi_imx->base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(spi_imx->base)) {
		ret = PTR_ERR(spi_imx->base);
		goto out_master_put;
	}

	spi_imx->irq = platform_get_irq(pdev, 0);
	if (spi_imx->irq < 0) {
		ret = -EINVAL;
		goto out_master_put;
	}

	ret = devm_request_irq(&pdev->dev, spi_imx->irq, spi_imx_isr, 0,
			       DRIVER_NAME, spi_imx);
	if (ret) {
		dev_err(&pdev->dev, "can't get irq%d: %d\n", spi_imx->irq, ret);
		goto out_master_put;
	}

	spi_imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
	if (IS_ERR(spi_imx->clk_ipg)) {
		ret = PTR_ERR(spi_imx->clk_ipg);
		goto out_master_put;
	}

	spi_imx->clk_per = devm_clk_get(&pdev->dev, "per");
	if (IS_ERR(spi_imx->clk_per)) {
		ret = PTR_ERR(spi_imx->clk_per);
		goto out_master_put;
	}

	ret = clk_prepare_enable(spi_imx->clk_per);
	if (ret)
		goto out_master_put;

	ret = clk_prepare_enable(spi_imx->clk_ipg);
	if (ret)
		goto out_put_per;

	spi_imx->spi_clk = clk_get_rate(spi_imx->clk_per);

	spi_imx->devtype_data->reset(spi_imx);

	spi_imx->devtype_data->intctrl(spi_imx, 0);

	master->dev.of_node = pdev->dev.of_node;
	ret = spi_bitbang_start(&spi_imx->bitbang);
	if (ret) {
		dev_err(&pdev->dev, "bitbang start failed with %d\n", ret);
		goto out_clk_put;
	}

	dev_info(&pdev->dev, "probed\n");

	clk_disable(spi_imx->clk_ipg);
	clk_disable(spi_imx->clk_per);
	return ret;

out_clk_put:
	clk_disable_unprepare(spi_imx->clk_ipg);
out_put_per:
	clk_disable_unprepare(spi_imx->clk_per);
out_master_put:
	spi_master_put(master);

	return ret;
}

/*
 * General clocks
 *
 * clk_get_rate
 */
static unsigned long lradc_clk_get_rate(struct clk *clk)
{
	return clk_get_rate(clk->parent) / 16;
}

static int omap_i2c_init(struct omap_i2c_dev *dev)
{
	u16 psc = 0, scll = 0, sclh = 0, buf = 0;
	u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
	unsigned long fclk_rate = 12000000;
	unsigned long timeout;
	unsigned long internal_clk = 0;
	struct clk *fclk;

	if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
		/* Disable I2C controller before soft reset */
		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
			omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
				~(OMAP_I2C_CON_EN));

		omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
		/* For some reason we need to set the EN bit before the
		 * reset done bit gets set. */
		timeout = jiffies + OMAP_I2C_TIMEOUT;
		omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
		while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
			 SYSS_RESETDONE_MASK)) {
			if (time_after(jiffies, timeout)) {
				dev_warn(dev->dev, "timeout waiting "
						"for controller reset\n");
				return -ETIMEDOUT;
			}
			msleep(1);
		}

		/* SYSC register is cleared by the reset; rewrite it */
		if (dev->rev == OMAP_I2C_REV_ON_2430) {

			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
					   SYSC_AUTOIDLE_MASK);

		} else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
			dev->syscstate = SYSC_AUTOIDLE_MASK;
			dev->syscstate |= SYSC_ENAWAKEUP_MASK;
			dev->syscstate |= (SYSC_IDLEMODE_SMART <<
			      __ffs(SYSC_SIDLEMODE_MASK));
			dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
			      __ffs(SYSC_CLOCKACTIVITY_MASK));

			omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
							dev->syscstate);
			/*
			 * Enabling all wakup sources to stop I2C freezing on
			 * WFI instruction.
			 * REVISIT: Some wkup sources might not be needed.
			 */
			dev->westate = OMAP_I2C_WE_ALL;
			omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
							dev->westate);
		}
	}
	omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);

	if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
		/*
		 * The I2C functional clock is the armxor_ck, so there's
		 * no need to get "armxor_ck" separately.  Now, if OMAP2420
		 * always returns 12MHz for the functional clock, we can
		 * do this bit unconditionally.
		 */
		fclk = clk_get(dev->dev, "fck");
		fclk_rate = clk_get_rate(fclk);
		clk_put(fclk);

		/* TRM for 5912 says the I2C clock must be prescaled to be
		 * between 7 - 12 MHz. The XOR input clock is typically
		 * 12, 13 or 19.2 MHz. So we should have code that produces:
		 *
		 * XOR MHz	Divider		Prescaler
		 * 12		1		0
		 * 13		2		1
		 * 19.2		2		1
		 */
		if (fclk_rate > 12000000)
			psc = fclk_rate / 12000000;
	}

	if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {

		/*
		 * HSI2C controller internal clk rate should be 19.2 Mhz for
		 * HS and for all modes on 2430. On 34xx we can use lower rate
		 * to get longer filter period for better noise suppression.
		 * The filter is iclk (fclk for HS) period.
		 */
		if (dev->speed > 400 ||
			       dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
			internal_clk = 19200;
		else if (dev->speed > 100)
			internal_clk = 9600;
		else
			internal_clk = 4000;
		fclk = clk_get(dev->dev, "fck");
		fclk_rate = clk_get_rate(fclk) / 1000;
		clk_put(fclk);
//.........这里部分代码省略.........

static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
{
	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);

	return clk_get_rate(pltfm_host->clk) / 256 / 16;
}

/*****************************************************************************
 * UART
 ****************************************************************************/
static unsigned long __init uart_get_clk_rate(struct clk *clk)
{
	clk_prepare_enable(clk);
	return clk_get_rate(clk);
}

static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
					 const char *fck_source,
					 const char *property,
					 const char **timer_name,
					 int posted)
{
	char name[10]; /* 10 = sizeof("gptXX_Xck0") */
	const char *oh_name = NULL;
	struct device_node *np;
	struct omap_hwmod *oh;
	struct resource irq, mem;
	struct clk *src;
	int r = 0;

	if (of_have_populated_dt()) {
		np = omap_get_timer_dt(omap_timer_match, property);
		if (!np)
			return -ENODEV;

		of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
		if (!oh_name)
			return -ENODEV;

		timer->irq = irq_of_parse_and_map(np, 0);
		if (!timer->irq)
			return -ENXIO;

		timer->io_base = of_iomap(np, 0);

		of_node_put(np);
	} else {
		if (omap_dm_timer_reserve_systimer(timer->id))
			return -ENODEV;

		sprintf(name, "timer%d", timer->id);
		oh_name = name;
	}

	oh = omap_hwmod_lookup(oh_name);
	if (!oh)
		return -ENODEV;

	*timer_name = oh->name;

	if (!of_have_populated_dt()) {
		r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL,
						   &irq);
		if (r)
			return -ENXIO;
		timer->irq = irq.start;

		r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL,
						   &mem);
		if (r)
			return -ENXIO;

		/* Static mapping, never released */
		timer->io_base = ioremap(mem.start, mem.end - mem.start);
	}

	if (!timer->io_base)
		return -ENXIO;

	/* After the dmtimer is using hwmod these clocks won't be needed */
	timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
	if (IS_ERR(timer->fclk))
		return PTR_ERR(timer->fclk);

	src = clk_get(NULL, fck_source);
	if (IS_ERR(src))
		return PTR_ERR(src);

	if (clk_get_parent(timer->fclk) != src) {
		r = clk_set_parent(timer->fclk, src);
		if (r < 0) {
			pr_warn("%s: %s cannot set source\n", __func__,
				oh->name);
			clk_put(src);
			return r;
		}
	}

	clk_put(src);

	omap_hwmod_setup_one(oh_name);
	omap_hwmod_enable(oh);
	__omap_dm_timer_init_regs(timer);

	if (posted)
		__omap_dm_timer_enable_posted(timer);

	/* Check that the intended posted configuration matches the actual */
	if (posted != timer->posted)
		return -EINVAL;

	timer->rate = clk_get_rate(timer->fclk);
	timer->reserved = 1;

	return r;
}