Author | Tokens | Token Proportion | Commits | Commit Proportion |
---|---|---|---|---|
Shawn Guo | 1117 | 55.16% | 1 | 4.35% |
Frank Li | 292 | 14.42% | 1 | 4.35% |
Anson Huang | 205 | 10.12% | 8 | 34.78% |
Trent Piepho | 194 | 9.58% | 1 | 4.35% |
Sanchayan Maity | 88 | 4.35% | 2 | 8.70% |
Stefan Eichenberger | 49 | 2.42% | 1 | 4.35% |
Bryan O'Donoghue | 30 | 1.48% | 1 | 4.35% |
Alexandre Belloni | 21 | 1.04% | 2 | 8.70% |
Thierry Reding | 10 | 0.49% | 1 | 4.35% |
Stefan Agner | 7 | 0.35% | 1 | 4.35% |
Guy Shapiro | 5 | 0.25% | 1 | 4.35% |
Pan Bian | 3 | 0.15% | 1 | 4.35% |
Fabio Estevam | 3 | 0.15% | 1 | 4.35% |
Bartosz Golaszewski | 1 | 0.05% | 1 | 4.35% |
Total | 2025 | 23 |
// SPDX-License-Identifier: GPL-2.0+ // // Copyright (C) 2011-2012 Freescale Semiconductor, Inc. #include <linux/init.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include <linux/platform_device.h> #include <linux/pm_wakeirq.h> #include <linux/rtc.h> #include <linux/clk.h> #include <linux/mfd/syscon.h> #include <linux/regmap.h> #define SNVS_LPREGISTER_OFFSET 0x34 /* These register offsets are relative to LP (Low Power) range */ #define SNVS_LPCR 0x04 #define SNVS_LPSR 0x18 #define SNVS_LPSRTCMR 0x1c #define SNVS_LPSRTCLR 0x20 #define SNVS_LPTAR 0x24 #define SNVS_LPPGDR 0x30 #define SNVS_LPCR_SRTC_ENV (1 << 0) #define SNVS_LPCR_LPTA_EN (1 << 1) #define SNVS_LPCR_LPWUI_EN (1 << 3) #define SNVS_LPSR_LPTA (1 << 0) #define SNVS_LPPGDR_INIT 0x41736166 #define CNTR_TO_SECS_SH 15 /* The maximum RTC clock cycles that are allowed to pass between two * consecutive clock counter register reads. If the values are corrupted a * bigger difference is expected. The RTC frequency is 32kHz. With 320 cycles * we end at 10ms which should be enough for most cases. If it once takes * longer than expected we do a retry. */ #define MAX_RTC_READ_DIFF_CYCLES 320 struct snvs_rtc_data { struct rtc_device *rtc; struct regmap *regmap; int offset; int irq; struct clk *clk; }; /* Read 64 bit timer register, which could be in inconsistent state */ static u64 rtc_read_lpsrt(struct snvs_rtc_data *data) { u32 msb, lsb; regmap_read(data->regmap, data->offset + SNVS_LPSRTCMR, &msb); regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &lsb); return (u64)msb << 32 | lsb; } /* Read the secure real time counter, taking care to deal with the cases of the * counter updating while being read. */ static u32 rtc_read_lp_counter(struct snvs_rtc_data *data) { u64 read1, read2; s64 diff; unsigned int timeout = 100; /* As expected, the registers might update between the read of the LSB * reg and the MSB reg. It's also possible that one register might be * in partially modified state as well. */ read1 = rtc_read_lpsrt(data); do { read2 = read1; read1 = rtc_read_lpsrt(data); diff = read1 - read2; } while (((diff < 0) || (diff > MAX_RTC_READ_DIFF_CYCLES)) && --timeout); if (!timeout) dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n"); /* Convert 47-bit counter to 32-bit raw second count */ return (u32) (read1 >> CNTR_TO_SECS_SH); } /* Just read the lsb from the counter, dealing with inconsistent state */ static int rtc_read_lp_counter_lsb(struct snvs_rtc_data *data, u32 *lsb) { u32 count1, count2; s32 diff; unsigned int timeout = 100; regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1); do { count2 = count1; regmap_read(data->regmap, data->offset + SNVS_LPSRTCLR, &count1); diff = count1 - count2; } while (((diff < 0) || (diff > MAX_RTC_READ_DIFF_CYCLES)) && --timeout); if (!timeout) { dev_err(&data->rtc->dev, "Timeout trying to get valid LPSRT Counter read\n"); return -ETIMEDOUT; } *lsb = count1; return 0; } static int rtc_write_sync_lp(struct snvs_rtc_data *data) { u32 count1, count2; u32 elapsed; unsigned int timeout = 1000; int ret; ret = rtc_read_lp_counter_lsb(data, &count1); if (ret) return ret; /* Wait for 3 CKIL cycles, about 61.0-91.5 µs */ do { ret = rtc_read_lp_counter_lsb(data, &count2); if (ret) return ret; elapsed = count2 - count1; /* wrap around _is_ handled! */ } while (elapsed < 3 && --timeout); if (!timeout) { dev_err(&data->rtc->dev, "Timeout waiting for LPSRT Counter to change\n"); return -ETIMEDOUT; } return 0; } static int snvs_rtc_enable(struct snvs_rtc_data *data, bool enable) { int timeout = 1000; u32 lpcr; regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_SRTC_ENV, enable ? SNVS_LPCR_SRTC_ENV : 0); while (--timeout) { regmap_read(data->regmap, data->offset + SNVS_LPCR, &lpcr); if (enable) { if (lpcr & SNVS_LPCR_SRTC_ENV) break; } else { if (!(lpcr & SNVS_LPCR_SRTC_ENV)) break; } } if (!timeout) return -ETIMEDOUT; return 0; } static int snvs_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct snvs_rtc_data *data = dev_get_drvdata(dev); unsigned long time; int ret; ret = clk_enable(data->clk); if (ret) return ret; time = rtc_read_lp_counter(data); rtc_time64_to_tm(time, tm); clk_disable(data->clk); return 0; } static int snvs_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct snvs_rtc_data *data = dev_get_drvdata(dev); unsigned long time = rtc_tm_to_time64(tm); int ret; ret = clk_enable(data->clk); if (ret) return ret; /* Disable RTC first */ ret = snvs_rtc_enable(data, false); if (ret) return ret; /* Write 32-bit time to 47-bit timer, leaving 15 LSBs blank */ regmap_write(data->regmap, data->offset + SNVS_LPSRTCLR, time << CNTR_TO_SECS_SH); regmap_write(data->regmap, data->offset + SNVS_LPSRTCMR, time >> (32 - CNTR_TO_SECS_SH)); /* Enable RTC again */ ret = snvs_rtc_enable(data, true); clk_disable(data->clk); return ret; } static int snvs_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct snvs_rtc_data *data = dev_get_drvdata(dev); u32 lptar, lpsr; int ret; ret = clk_enable(data->clk); if (ret) return ret; regmap_read(data->regmap, data->offset + SNVS_LPTAR, &lptar); rtc_time64_to_tm(lptar, &alrm->time); regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr); alrm->pending = (lpsr & SNVS_LPSR_LPTA) ? 1 : 0; clk_disable(data->clk); return 0; } static int snvs_rtc_alarm_irq_enable(struct device *dev, unsigned int enable) { struct snvs_rtc_data *data = dev_get_drvdata(dev); int ret; ret = clk_enable(data->clk); if (ret) return ret; regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN), enable ? (SNVS_LPCR_LPTA_EN | SNVS_LPCR_LPWUI_EN) : 0); ret = rtc_write_sync_lp(data); clk_disable(data->clk); return ret; } static int snvs_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) { struct snvs_rtc_data *data = dev_get_drvdata(dev); unsigned long time = rtc_tm_to_time64(&alrm->time); int ret; ret = clk_enable(data->clk); if (ret) return ret; regmap_update_bits(data->regmap, data->offset + SNVS_LPCR, SNVS_LPCR_LPTA_EN, 0); ret = rtc_write_sync_lp(data); if (ret) return ret; regmap_write(data->regmap, data->offset + SNVS_LPTAR, time); /* Clear alarm interrupt status bit */ regmap_write(data->regmap, data->offset + SNVS_LPSR, SNVS_LPSR_LPTA); clk_disable(data->clk); return snvs_rtc_alarm_irq_enable(dev, alrm->enabled); } static const struct rtc_class_ops snvs_rtc_ops = { .read_time = snvs_rtc_read_time, .set_time = snvs_rtc_set_time, .read_alarm = snvs_rtc_read_alarm, .set_alarm = snvs_rtc_set_alarm, .alarm_irq_enable = snvs_rtc_alarm_irq_enable, }; static irqreturn_t snvs_rtc_irq_handler(int irq, void *dev_id) { struct device *dev = dev_id; struct snvs_rtc_data *data = dev_get_drvdata(dev); u32 lpsr; u32 events = 0; clk_enable(data->clk); regmap_read(data->regmap, data->offset + SNVS_LPSR, &lpsr); if (lpsr & SNVS_LPSR_LPTA) { events |= (RTC_AF | RTC_IRQF); /* RTC alarm should be one-shot */ snvs_rtc_alarm_irq_enable(dev, 0); rtc_update_irq(data->rtc, 1, events); } /* clear interrupt status */ regmap_write(data->regmap, data->offset + SNVS_LPSR, lpsr); clk_disable(data->clk); return events ? IRQ_HANDLED : IRQ_NONE; } static const struct regmap_config snvs_rtc_config = { .reg_bits = 32, .val_bits = 32, .reg_stride = 4, }; static void snvs_rtc_action(void *data) { clk_disable_unprepare(data); } static int snvs_rtc_probe(struct platform_device *pdev) { struct snvs_rtc_data *data; int ret; void __iomem *mmio; data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); if (!data) return -ENOMEM; data->rtc = devm_rtc_allocate_device(&pdev->dev); if (IS_ERR(data->rtc)) return PTR_ERR(data->rtc); data->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap"); if (IS_ERR(data->regmap)) { dev_warn(&pdev->dev, "snvs rtc: you use old dts file, please update it\n"); mmio = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(mmio)) return PTR_ERR(mmio); data->regmap = devm_regmap_init_mmio(&pdev->dev, mmio, &snvs_rtc_config); } else { data->offset = SNVS_LPREGISTER_OFFSET; of_property_read_u32(pdev->dev.of_node, "offset", &data->offset); } if (IS_ERR(data->regmap)) { dev_err(&pdev->dev, "Can't find snvs syscon\n"); return -ENODEV; } data->irq = platform_get_irq(pdev, 0); if (data->irq < 0) return data->irq; data->clk = devm_clk_get(&pdev->dev, "snvs-rtc"); if (IS_ERR(data->clk)) { data->clk = NULL; } else { ret = clk_prepare_enable(data->clk); if (ret) { dev_err(&pdev->dev, "Could not prepare or enable the snvs clock\n"); return ret; } } ret = devm_add_action_or_reset(&pdev->dev, snvs_rtc_action, data->clk); if (ret) return ret; platform_set_drvdata(pdev, data); /* Initialize glitch detect */ regmap_write(data->regmap, data->offset + SNVS_LPPGDR, SNVS_LPPGDR_INIT); /* Clear interrupt status */ regmap_write(data->regmap, data->offset + SNVS_LPSR, 0xffffffff); /* Enable RTC */ ret = snvs_rtc_enable(data, true); if (ret) { dev_err(&pdev->dev, "failed to enable rtc %d\n", ret); return ret; } device_init_wakeup(&pdev->dev, true); ret = dev_pm_set_wake_irq(&pdev->dev, data->irq); if (ret) dev_err(&pdev->dev, "failed to enable irq wake\n"); ret = devm_request_irq(&pdev->dev, data->irq, snvs_rtc_irq_handler, IRQF_SHARED, "rtc alarm", &pdev->dev); if (ret) { dev_err(&pdev->dev, "failed to request irq %d: %d\n", data->irq, ret); return ret; } data->rtc->ops = &snvs_rtc_ops; data->rtc->range_max = U32_MAX; return devm_rtc_register_device(data->rtc); } static int __maybe_unused snvs_rtc_suspend_noirq(struct device *dev) { struct snvs_rtc_data *data = dev_get_drvdata(dev); clk_disable(data->clk); return 0; } static int __maybe_unused snvs_rtc_resume_noirq(struct device *dev) { struct snvs_rtc_data *data = dev_get_drvdata(dev); if (data->clk) return clk_enable(data->clk); return 0; } static const struct dev_pm_ops snvs_rtc_pm_ops = { SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(snvs_rtc_suspend_noirq, snvs_rtc_resume_noirq) }; static const struct of_device_id snvs_dt_ids[] = { { .compatible = "fsl,sec-v4.0-mon-rtc-lp", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, snvs_dt_ids); static struct platform_driver snvs_rtc_driver = { .driver = { .name = "snvs_rtc", .pm = &snvs_rtc_pm_ops, .of_match_table = snvs_dt_ids, }, .probe = snvs_rtc_probe, }; module_platform_driver(snvs_rtc_driver); MODULE_AUTHOR("Freescale Semiconductor, Inc."); MODULE_DESCRIPTION("Freescale SNVS RTC Driver"); MODULE_LICENSE("GPL");
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