On Mon, Feb 26, 2018 at 05:56:27PM +0300, Eugeniy Paltsev wrote: > +/* > + * Synopsys DesignWare AXI DMA Controller driver. > + * > + * Copyright (C) 2017-2018 Synopsys, Inc. (www.synopsys.com) > + * Author: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com> > + * > + * SPDX-License-Identifier: GPL-2.0 > + */ This needs to be in below style // SPDX-License-Identifier: GPL-2.0 // Copyright (C) .... /* * other things u want to add */ > +#define DRV_NAME "axi_dw_dmac" how about use KBUILD_MODNAME here? > +static enum dma_status > +dma_chan_tx_status(struct dma_chan *dchan, dma_cookie_t cookie, > + struct dma_tx_state *txstate) > +{ > + struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan); > + enum dma_status ret; > + > + ret = dma_cookie_status(dchan, cookie, txstate); > + > + if (chan->is_paused && ret == DMA_IN_PROGRESS) > + return DMA_PAUSED; > + > + return ret; nitpick, how about if (chan->is_paused && ret == DMA_IN_PROGRESS) ret = DMA_PAUSED; return ret; that way we have single point of return. > +static int dma_chan_alloc_chan_resources(struct dma_chan *dchan) > +{ > + struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan); > + > + /* ASSERT: channel is idle */ > + if (axi_chan_is_hw_enable(chan)) { > + dev_err(chan2dev(chan), "%s is non-idle!\n", > + axi_chan_name(chan)); > + return -EBUSY; > + } > + > + dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan)); > + > + dma_cookie_init(dchan); This is already done as part of vchan_init(), so why is it called explicitly and why is that not invoked here? > +static void dma_chan_free_chan_resources(struct dma_chan *dchan) > +{ > + struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan); > + > + /* ASSERT: channel is idle */ > + if (axi_chan_is_hw_enable(chan)) > + dev_err(dchan2dev(dchan), "%s is non-idle!\n", > + axi_chan_name(chan)); > + > + axi_chan_disable(chan); > + axi_chan_irq_disable(chan, DWAXIDMAC_IRQ_ALL); > + > + vchan_free_chan_resources(&chan->vc); > + > + dev_vdbg(dchan2dev(dchan), "%s: free resources, descriptor still allocated: %u\n", making the string in subsequent line make it lesser than 80 chars, here and few other places can benefit.. > +static irqreturn_t dw_axi_dma_intretupt(int irq, void *dev_id) /s/intretupt/interrupt/ ? > +static int axi_dma_resume(struct axi_dma_chip *chip) > +{ > + int ret = 0; superfluous init > +static int parse_device_properties(struct axi_dma_chip *chip) > +{ > + struct device *dev = chip->dev; > + u32 tmp, carr[DMAC_MAX_CHANNELS]; > + int ret; > + > + ret = device_property_read_u32(dev, "dma-channels", &tmp); > + if (ret) > + return ret; > + if (tmp == 0 || tmp > DMAC_MAX_CHANNELS) > + return -EINVAL; > + > + chip->dw->hdata->nr_channels = tmp; > + > + ret = device_property_read_u32(dev, "snps,dma-masters", &tmp); why is it snps,... shouldn't it be only dma-masters? > +enum { > + DWAXIDMAC_ARWLEN_1 = 0x0, > + DWAXIDMAC_ARWLEN_2 = 0x1, > + DWAXIDMAC_ARWLEN_4 = 0x3, > + DWAXIDMAC_ARWLEN_8 = 0x7, > + DWAXIDMAC_ARWLEN_16 = 0xF, > + DWAXIDMAC_ARWLEN_32 = 0x1F, > + DWAXIDMAC_ARWLEN_64 = 0x3F, > + DWAXIDMAC_ARWLEN_128 = 0x7F, > + DWAXIDMAC_ARWLEN_256 = 0xFF, GENMASK() for these? -- ~Vinod