diff options
Diffstat (limited to 'drivers/net/can/mscan')
| -rw-r--r-- | drivers/net/can/mscan/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mpc5xxx_can.c | 290 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mscan.c | 35 | ||||
| -rw-r--r-- | drivers/net/can/mscan/mscan.h | 12 |
4 files changed, 204 insertions, 135 deletions
diff --git a/drivers/net/can/mscan/Kconfig b/drivers/net/can/mscan/Kconfig index d38706958af..81c71171949 100644 --- a/drivers/net/can/mscan/Kconfig +++ b/drivers/net/can/mscan/Kconfig @@ -1,5 +1,5 @@ config CAN_MSCAN - depends on CAN_DEV && (PPC || M68K) + depends on PPC tristate "Support for Freescale MSCAN based chips" ---help--- The Motorola Scalable Controller Area Network (MSCAN) definition diff --git a/drivers/net/can/mscan/mpc5xxx_can.c b/drivers/net/can/mscan/mpc5xxx_can.c index 668850e441d..44725296f72 100644 --- a/drivers/net/can/mscan/mpc5xxx_can.c +++ b/drivers/net/can/mscan/mpc5xxx_can.c @@ -16,8 +16,7 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include <linux/kernel.h> @@ -40,6 +39,7 @@ struct mpc5xxx_can_data { unsigned int type; u32 (*get_clock)(struct platform_device *ofdev, const char *clock_name, int *mscan_clksrc); + void (*put_clock)(struct platform_device *ofdev); }; #ifdef CONFIG_PPC_MPC52xx @@ -108,132 +108,170 @@ static u32 mpc52xx_can_get_clock(struct platform_device *ofdev, #endif /* CONFIG_PPC_MPC52xx */ #ifdef CONFIG_PPC_MPC512x -struct mpc512x_clockctl { - u32 spmr; /* System PLL Mode Reg */ - u32 sccr[2]; /* System Clk Ctrl Reg 1 & 2 */ - u32 scfr1; /* System Clk Freq Reg 1 */ - u32 scfr2; /* System Clk Freq Reg 2 */ - u32 reserved; - u32 bcr; /* Bread Crumb Reg */ - u32 pccr[12]; /* PSC Clk Ctrl Reg 0-11 */ - u32 spccr; /* SPDIF Clk Ctrl Reg */ - u32 cccr; /* CFM Clk Ctrl Reg */ - u32 dccr; /* DIU Clk Cnfg Reg */ - u32 mccr[4]; /* MSCAN Clk Ctrl Reg 1-3 */ -}; - -static struct of_device_id mpc512x_clock_ids[] = { - { .compatible = "fsl,mpc5121-clock", }, - {} -}; - static u32 mpc512x_can_get_clock(struct platform_device *ofdev, - const char *clock_name, int *mscan_clksrc) + const char *clock_source, int *mscan_clksrc) { - struct mpc512x_clockctl __iomem *clockctl; - struct device_node *np_clock; - struct clk *sys_clk, *ref_clk; - int plen, clockidx, clocksrc = -1; - u32 sys_freq, val, clockdiv = 1, freq = 0; - const u32 *pval; - - np_clock = of_find_matching_node(NULL, mpc512x_clock_ids); - if (!np_clock) { - dev_err(&ofdev->dev, "couldn't find clock node\n"); - return 0; + struct device_node *np; + u32 clockdiv; + enum { + CLK_FROM_AUTO, + CLK_FROM_IPS, + CLK_FROM_SYS, + CLK_FROM_REF, + } clk_from; + struct clk *clk_in, *clk_can; + unsigned long freq_calc; + struct mscan_priv *priv; + struct clk *clk_ipg; + + /* the caller passed in the clock source spec that was read from + * the device tree, get the optional clock divider as well + */ + np = ofdev->dev.of_node; + clockdiv = 1; + of_property_read_u32(np, "fsl,mscan-clock-divider", &clockdiv); + dev_dbg(&ofdev->dev, "device tree specs: clk src[%s] div[%d]\n", + clock_source ? clock_source : "<NULL>", clockdiv); + + /* when clock-source is 'ip', the CANCTL1[CLKSRC] bit needs to + * get set, and the 'ips' clock is the input to the MSCAN + * component + * + * for clock-source values of 'ref' or 'sys' the CANCTL1[CLKSRC] + * bit needs to get cleared, an optional clock-divider may have + * been specified (the default value is 1), the appropriate + * MSCAN related MCLK is the input to the MSCAN component + * + * in the absence of a clock-source spec, first an optimal clock + * gets determined based on the 'sys' clock, if that fails the + * 'ref' clock is used + */ + clk_from = CLK_FROM_AUTO; + if (clock_source) { + /* interpret the device tree's spec for the clock source */ + if (!strcmp(clock_source, "ip")) + clk_from = CLK_FROM_IPS; + else if (!strcmp(clock_source, "sys")) + clk_from = CLK_FROM_SYS; + else if (!strcmp(clock_source, "ref")) + clk_from = CLK_FROM_REF; + else + goto err_invalid; + dev_dbg(&ofdev->dev, "got a clk source spec[%d]\n", clk_from); } - clockctl = of_iomap(np_clock, 0); - if (!clockctl) { - dev_err(&ofdev->dev, "couldn't map clock registers\n"); - goto exit_put; + if (clk_from == CLK_FROM_AUTO) { + /* no spec so far, try the 'sys' clock; round to the + * next MHz and see if we can get a multiple of 16MHz + */ + dev_dbg(&ofdev->dev, "no clk source spec, trying SYS\n"); + clk_in = devm_clk_get(&ofdev->dev, "sys"); + if (IS_ERR(clk_in)) + goto err_notavail; + freq_calc = clk_get_rate(clk_in); + freq_calc += 499999; + freq_calc /= 1000000; + freq_calc *= 1000000; + if ((freq_calc % 16000000) == 0) { + clk_from = CLK_FROM_SYS; + clockdiv = freq_calc / 16000000; + dev_dbg(&ofdev->dev, + "clk fit, sys[%lu] div[%d] freq[%lu]\n", + freq_calc, clockdiv, freq_calc / clockdiv); + } + } + if (clk_from == CLK_FROM_AUTO) { + /* no spec so far, use the 'ref' clock */ + dev_dbg(&ofdev->dev, "no clk source spec, trying REF\n"); + clk_in = devm_clk_get(&ofdev->dev, "ref"); + if (IS_ERR(clk_in)) + goto err_notavail; + clk_from = CLK_FROM_REF; + freq_calc = clk_get_rate(clk_in); + dev_dbg(&ofdev->dev, + "clk fit, ref[%lu] (no div) freq[%lu]\n", + freq_calc, freq_calc); } - /* Determine the MSCAN device index from the physical address */ - pval = of_get_property(ofdev->dev.of_node, "reg", &plen); - BUG_ON(!pval || plen < sizeof(*pval)); - clockidx = (*pval & 0x80) ? 1 : 0; - if (*pval & 0x2000) - clockidx += 2; - - /* - * Clock source and divider selection: 3 different clock sources - * can be selected: "ip", "ref" or "sys". For the latter two, a - * clock divider can be defined as well. If the clock source is - * not specified by the device tree, we first try to find an - * optimal CAN source clock based on the system clock. If that - * is not posslible, the reference clock will be used. + /* select IPS or MCLK as the MSCAN input (returned to the caller), + * setup the MCLK mux source and rate if applicable, apply the + * optionally specified or derived above divider, and determine + * the actual resulting clock rate to return to the caller */ - if (clock_name && !strcmp(clock_name, "ip")) { + switch (clk_from) { + case CLK_FROM_IPS: + clk_can = devm_clk_get(&ofdev->dev, "ips"); + if (IS_ERR(clk_can)) + goto err_notavail; + priv = netdev_priv(dev_get_drvdata(&ofdev->dev)); + priv->clk_can = clk_can; + freq_calc = clk_get_rate(clk_can); *mscan_clksrc = MSCAN_CLKSRC_IPS; - freq = mpc5xxx_get_bus_frequency(ofdev->dev.of_node); - } else { + dev_dbg(&ofdev->dev, "clk from IPS, clksrc[%d] freq[%lu]\n", + *mscan_clksrc, freq_calc); + break; + case CLK_FROM_SYS: + case CLK_FROM_REF: + clk_can = devm_clk_get(&ofdev->dev, "mclk"); + if (IS_ERR(clk_can)) + goto err_notavail; + priv = netdev_priv(dev_get_drvdata(&ofdev->dev)); + priv->clk_can = clk_can; + if (clk_from == CLK_FROM_SYS) + clk_in = devm_clk_get(&ofdev->dev, "sys"); + if (clk_from == CLK_FROM_REF) + clk_in = devm_clk_get(&ofdev->dev, "ref"); + if (IS_ERR(clk_in)) + goto err_notavail; + clk_set_parent(clk_can, clk_in); + freq_calc = clk_get_rate(clk_in); + freq_calc /= clockdiv; + clk_set_rate(clk_can, freq_calc); + freq_calc = clk_get_rate(clk_can); *mscan_clksrc = MSCAN_CLKSRC_BUS; - - pval = of_get_property(ofdev->dev.of_node, - "fsl,mscan-clock-divider", &plen); - if (pval && plen == sizeof(*pval)) - clockdiv = *pval; - if (!clockdiv) - clockdiv = 1; - - if (!clock_name || !strcmp(clock_name, "sys")) { - sys_clk = clk_get(&ofdev->dev, "sys_clk"); - if (IS_ERR(sys_clk)) { - dev_err(&ofdev->dev, "couldn't get sys_clk\n"); - goto exit_unmap; - } - /* Get and round up/down sys clock rate */ - sys_freq = 1000000 * - ((clk_get_rate(sys_clk) + 499999) / 1000000); - - if (!clock_name) { - /* A multiple of 16 MHz would be optimal */ - if ((sys_freq % 16000000) == 0) { - clocksrc = 0; - clockdiv = sys_freq / 16000000; - freq = sys_freq / clockdiv; - } - } else { - clocksrc = 0; - freq = sys_freq / clockdiv; - } - } - - if (clocksrc < 0) { - ref_clk = clk_get(&ofdev->dev, "ref_clk"); - if (IS_ERR(ref_clk)) { - dev_err(&ofdev->dev, "couldn't get ref_clk\n"); - goto exit_unmap; - } - clocksrc = 1; - freq = clk_get_rate(ref_clk) / clockdiv; - } + dev_dbg(&ofdev->dev, "clk from MCLK, clksrc[%d] freq[%lu]\n", + *mscan_clksrc, freq_calc); + break; + default: + goto err_invalid; } - /* Disable clock */ - out_be32(&clockctl->mccr[clockidx], 0x0); - if (clocksrc >= 0) { - /* Set source and divider */ - val = (clocksrc << 14) | ((clockdiv - 1) << 17); - out_be32(&clockctl->mccr[clockidx], val); - /* Enable clock */ - out_be32(&clockctl->mccr[clockidx], val | 0x10000); - } + /* the above clk_can item is used for the bitrate, access to + * the peripheral's register set needs the clk_ipg item + */ + clk_ipg = devm_clk_get(&ofdev->dev, "ipg"); + if (IS_ERR(clk_ipg)) + goto err_notavail_ipg; + if (clk_prepare_enable(clk_ipg)) + goto err_notavail_ipg; + priv = netdev_priv(dev_get_drvdata(&ofdev->dev)); + priv->clk_ipg = clk_ipg; + + /* return the determined clock source rate */ + return freq_calc; + +err_invalid: + dev_err(&ofdev->dev, "invalid clock source specification\n"); + /* clock source rate could not get determined */ + return 0; - /* Enable MSCAN clock domain */ - val = in_be32(&clockctl->sccr[1]); - if (!(val & (1 << 25))) - out_be32(&clockctl->sccr[1], val | (1 << 25)); +err_notavail: + dev_err(&ofdev->dev, "cannot acquire or setup bitrate clock source\n"); + /* clock source rate could not get determined */ + return 0; - dev_dbg(&ofdev->dev, "using '%s' with frequency divider %d\n", - *mscan_clksrc == MSCAN_CLKSRC_IPS ? "ips_clk" : - clocksrc == 1 ? "ref_clk" : "sys_clk", clockdiv); +err_notavail_ipg: + dev_err(&ofdev->dev, "cannot acquire or setup register clock\n"); + /* clock source rate could not get determined */ + return 0; +} -exit_unmap: - iounmap(clockctl); -exit_put: - of_node_put(np_clock); - return freq; +static void mpc512x_can_put_clock(struct platform_device *ofdev) +{ + struct mscan_priv *priv; + + priv = netdev_priv(dev_get_drvdata(&ofdev->dev)); + if (priv->clk_ipg) + clk_disable_unprepare(priv->clk_ipg); } #else /* !CONFIG_PPC_MPC512x */ static u32 mpc512x_can_get_clock(struct platform_device *ofdev, @@ -241,6 +279,7 @@ static u32 mpc512x_can_get_clock(struct platform_device *ofdev, { return 0; } +#define mpc512x_can_put_clock NULL #endif /* CONFIG_PPC_MPC512x */ static const struct of_device_id mpc5xxx_can_table[]; @@ -277,6 +316,8 @@ static int mpc5xxx_can_probe(struct platform_device *ofdev) dev = alloc_mscandev(); if (!dev) goto exit_dispose_irq; + platform_set_drvdata(ofdev, dev); + SET_NETDEV_DEV(dev, &ofdev->dev); priv = netdev_priv(dev); priv->reg_base = base; @@ -293,8 +334,6 @@ static int mpc5xxx_can_probe(struct platform_device *ofdev) goto exit_free_mscan; } - SET_NETDEV_DEV(dev, &ofdev->dev); - err = register_mscandev(dev, mscan_clksrc); if (err) { dev_err(&ofdev->dev, "registering %s failed (err=%d)\n", @@ -302,8 +341,6 @@ static int mpc5xxx_can_probe(struct platform_device *ofdev) goto exit_free_mscan; } - dev_set_drvdata(&ofdev->dev, dev); - dev_info(&ofdev->dev, "MSCAN at 0x%p, irq %d, clock %d Hz\n", priv->reg_base, dev->irq, priv->can.clock.freq); @@ -321,12 +358,17 @@ exit_unmap_mem: static int mpc5xxx_can_remove(struct platform_device *ofdev) { - struct net_device *dev = dev_get_drvdata(&ofdev->dev); + const struct of_device_id *match; + const struct mpc5xxx_can_data *data; + struct net_device *dev = platform_get_drvdata(ofdev); struct mscan_priv *priv = netdev_priv(dev); - dev_set_drvdata(&ofdev->dev, NULL); + match = of_match_device(mpc5xxx_can_table, &ofdev->dev); + data = match ? match->data : NULL; unregister_mscandev(dev); + if (data && data->put_clock) + data->put_clock(ofdev); iounmap(priv->reg_base); irq_dispose_mapping(dev->irq); free_candev(dev); @@ -338,7 +380,7 @@ static int mpc5xxx_can_remove(struct platform_device *ofdev) static struct mscan_regs saved_regs; static int mpc5xxx_can_suspend(struct platform_device *ofdev, pm_message_t state) { - struct net_device *dev = dev_get_drvdata(&ofdev->dev); + struct net_device *dev = platform_get_drvdata(ofdev); struct mscan_priv *priv = netdev_priv(dev); struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; @@ -349,7 +391,7 @@ static int mpc5xxx_can_suspend(struct platform_device *ofdev, pm_message_t state static int mpc5xxx_can_resume(struct platform_device *ofdev) { - struct net_device *dev = dev_get_drvdata(&ofdev->dev); + struct net_device *dev = platform_get_drvdata(ofdev); struct mscan_priv *priv = netdev_priv(dev); struct mscan_regs *regs = (struct mscan_regs *)priv->reg_base; @@ -379,11 +421,13 @@ static int mpc5xxx_can_resume(struct platform_device *ofdev) static const struct mpc5xxx_can_data mpc5200_can_data = { .type = MSCAN_TYPE_MPC5200, .get_clock = mpc52xx_can_get_clock, + /* .put_clock not applicable */ }; static const struct mpc5xxx_can_data mpc5121_can_data = { .type = MSCAN_TYPE_MPC5121, .get_clock = mpc512x_can_get_clock, + .put_clock = mpc512x_can_put_clock, }; static const struct of_device_id mpc5xxx_can_table[] = { diff --git a/drivers/net/can/mscan/mscan.c b/drivers/net/can/mscan/mscan.c index e6b40954e20..e0c9be5e2ab 100644 --- a/drivers/net/can/mscan/mscan.c +++ b/drivers/net/can/mscan/mscan.c @@ -16,8 +16,7 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #include <linux/kernel.h> @@ -573,10 +572,21 @@ static int mscan_open(struct net_device *dev) struct mscan_priv *priv = netdev_priv(dev); struct mscan_regs __iomem *regs = priv->reg_base; + if (priv->clk_ipg) { + ret = clk_prepare_enable(priv->clk_ipg); + if (ret) + goto exit_retcode; + } + if (priv->clk_can) { + ret = clk_prepare_enable(priv->clk_can); + if (ret) + goto exit_dis_ipg_clock; + } + /* common open */ ret = open_candev(dev); if (ret) - return ret; + goto exit_dis_can_clock; napi_enable(&priv->napi); @@ -604,6 +614,13 @@ exit_free_irq: exit_napi_disable: napi_disable(&priv->napi); close_candev(dev); +exit_dis_can_clock: + if (priv->clk_can) + clk_disable_unprepare(priv->clk_can); +exit_dis_ipg_clock: + if (priv->clk_ipg) + clk_disable_unprepare(priv->clk_ipg); +exit_retcode: return ret; } @@ -621,13 +638,19 @@ static int mscan_close(struct net_device *dev) close_candev(dev); free_irq(dev->irq, dev); + if (priv->clk_can) + clk_disable_unprepare(priv->clk_can); + if (priv->clk_ipg) + clk_disable_unprepare(priv->clk_ipg); + return 0; } static const struct net_device_ops mscan_netdev_ops = { - .ndo_open = mscan_open, - .ndo_stop = mscan_close, - .ndo_start_xmit = mscan_start_xmit, + .ndo_open = mscan_open, + .ndo_stop = mscan_close, + .ndo_start_xmit = mscan_start_xmit, + .ndo_change_mtu = can_change_mtu, }; int register_mscandev(struct net_device *dev, int mscan_clksrc) diff --git a/drivers/net/can/mscan/mscan.h b/drivers/net/can/mscan/mscan.h index af2ed8baf0a..ad8e08f9c49 100644 --- a/drivers/net/can/mscan/mscan.h +++ b/drivers/net/can/mscan/mscan.h @@ -14,13 +14,13 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * along with this program; if not, see <http://www.gnu.org/licenses/>. */ #ifndef __MSCAN_H__ #define __MSCAN_H__ +#include <linux/clk.h> #include <linux/types.h> /* MSCAN control register 0 (CANCTL0) bits */ @@ -283,6 +283,8 @@ struct mscan_priv { unsigned int type; /* MSCAN type variants */ unsigned long flags; void __iomem *reg_base; /* ioremap'ed address to registers */ + struct clk *clk_ipg; /* clock for registers */ + struct clk *clk_can; /* clock for bitrates */ u8 shadow_statflg; u8 shadow_canrier; u8 cur_pri; @@ -294,8 +296,8 @@ struct mscan_priv { struct napi_struct napi; }; -extern struct net_device *alloc_mscandev(void); -extern int register_mscandev(struct net_device *dev, int mscan_clksrc); -extern void unregister_mscandev(struct net_device *dev); +struct net_device *alloc_mscandev(void); +int register_mscandev(struct net_device *dev, int mscan_clksrc); +void unregister_mscandev(struct net_device *dev); #endif /* __MSCAN_H__ */ |